Treatment with ramipril improves systolic function even in patients with mild systolic dysfunction and symptoms of heart failure after acute myocardial infarction.

BACKGROUND: Clinical signs of heart failure such as pulmonary rales and dyspnea, ventricular dysfunction, and ventricular arrhythmia are independent predictors of a poor prognosis after acute myocardial infarction (AMI). HYPOTHESIS: The study aimed to assess the effect of ramipril treatment on mildly depressed left ventricular (LV) systolic function, assessed by atrioventricular (AV) plane displacement in patients with congestive heart failure after AMI. METHODS: The study was a substudy in the Acute Infarction Ramipril Efficacy Study, a double-blind, randomized, place-bo-controlled trial of ramipril versus placebo in patients with symptoms of heart failure after AMI. In all, 56 patients were included in the main study, 4 refused to participate in the substudy, and 4 were excluded for logistical reasons. Echocardiography was performed at entry and after 6 months. Patients who underwent coronary artery bypass grafting during the follow-up period were excluded. RESULTS: At baseline, the patients had modest LV dysfunction, and mean AV plane displacement of 9.7 mm. During follow-up, AV plane displacement increased in ramipril-treated patients from 9.5 to 10.9 mm (p < 0.01). No statistically significant changes were seen in the placebo group. CONCLUSIONS: Ramipril improves LV systolic function in patients with clinical signs of heart failure and only modest systolic dysfunction after AMI. Measurement of AV plane displacement is a simple and reproducible method for detection of small changes in systolic function and may be used instead of ejection fraction in patients with poor image quality.

Assessment of left ventricular diastolic function from mitral annulus motion, a comparison with pulsed Doppler measurements in patients with heart failure.

Mitral and pulmonary venous flow velocity recordings are often used for the assessment of left ventricular diastolic function. These curves are, however, also influenced by other factors. To investigate whether mitral annulus motion carries additional information in this context, mitral annulus motion was compared to Doppler registrations of mitral and pulmonary flow velocities in 38 patients with heart failure (NYHA II-III) after myocardial infarction. Patients with an increased atrial contribution to mitral annulus motion (> 57%, n = 12) had a higher mitral late-to-early flow velocity ratio (A/E) and pulmonary systolic to diastolic filling ratio (< 0.01). Patients with atrial displacement above average for the group (> or = 5.1 mm, n = 19) had a higher mitral (A/E) ratio and pulmonary systolic to diastolic filling ratio than patients with a lower than average atrial component (P < 0.05). There was a significant correlation between a/T ratio and A/E ratio (r = 0.61, P < 0.001) and between pulmonary flow and transmitral flow (= 0.76, P < 0.001). We conclude that an increased atrial displacement of the mitral annulus is a frequent finding in patients with signs of left ventricular relaxation abnormality. There is a significant correlation between a/T ratio and A/E ratio but the information contained in the two indices are not identical.

Cardiovascular effects of dobutamine stress testing in women with suspected coronary artery disease.

OBJECTIVE: To investigate the central and peripheral haemodynamic response to dobutamine stress testing in women with suspected ischaemic heart disease and to seek an explanation for the hypotension phenomenon. DESIGN: 18 women aged 54-73 years were investigated with Doppler echocardiography and venous occlusion plethysmography during intravenous infusion of dobutamine 5-10 d after an episode of unstable angina. RESULTS: An average peak dose of 33 (SD 9.7) micrograms/kg/min was given. Heart rate and cardiac output increased by 49% and 59%, respectively (P < 0.001). Total and leg peripheral vascular resistance decreased by 44% and 26%, respectively (P < 0.001). Four patients developed hypotension (decrease in systolic blood pressure > 10 mm Hg), one of whom had a paradoxical bradycardia and two a low increase in cardiac output. Patients with hypotension had a more pronounced decrease in total peripheral vascular resistance but a similar change in leg peripheral vascular resistance compared with patients without hypotension. CONCLUSIONS: Dobutamine infusion leads to marked peripheral vasodilatation and an increase in cardiac output. Some patients experience hypotension during the test for reasons which include paradoxical vasovagal reactions and diminished capacity for adequate increase in cardiac output. There is also a disparity between the pattern of total and leg peripheral vascular resistance in patients with hypotension which might reflect a baroreceptor mediated compensatory increase in vasoconstrictor tone of muscle vessels not matched in other vascular territories.

Cardiovascular effects of dobutamine stress testing in healthy women.

Dobutamine echocardiography is frequently used for detection of coronary artery disease. The circulatory response in patients is known to some extent, but studies in normals are lacking. Hypotensive response during the test is a common side effect, the cause of which is unclear. The aim of this study was, therefore, to investigate the hemodynamic response to dobutamine in women without cardiovascular disease and interfering medications. Eleven healthy women, age 53-71 years, were investigated with Doppler echocardiography and venous occlusion plethysmography during intravenous infusion of increasing doses of dobutamine according to a standardized protocol. An average peak dose of 22 +/- 7.5 micrograms kg-1 min-1 was administered. Cardiac output increased by 93%, heart rate by 68%, and stroke volume by 15%, while peripheral vascular resistance decreased by approximately 50%. Systolic blood pressure remained unchanged and diastolic blood pressure decreased by 21%. One subject demonstrated a decreased systolic blood pressure exceeding 10 mmHg. Outflow obstruction from the left ventricle was seen in two subjects, one of whom had a slight decrease of 10 mmHg in systolic blood pressure. Subjects > 65 years demonstrated a less pronounced increase in heart rate, cardiac output, and decrease in peripheral vascular resistance compared with those < 65 years.

Exercise echocardiography and thallium 201 single-photon emission computed tomography in male patients after an episode of unstable coronary artery disease.

To compare modern, digital exercise echocardiography and thallium 201 single-photon emission computed tomography (SPECT) in patients with unstable coronary artery disease, 65 men unselected with regard to echocardiography were prospectively investigated 1 month after an episode of unstable angina or non-Q-wave myocardial infarction. Exercise echocardiography and 201Tl SPECT were performed on consecutive days in connection with a standard symptom-limited upright bicycle test and analyzed in a 9-segment model. Coronary angiography was performed in all but 1 patient and 60 patients had significant coronary lesions. Wall motion abnormalities were seen in 53 patients (81%) at rest and perfusion defects in 57 patients (88%) at the redistribution images. New or worsening of wall motion abnormalities were seen in 55 patients, either seated at peak exercise or recumbent after exercise, and 43 patients had reversible or partially reversible 201Tl scintigraphic defects (P = .02). The segmental agreement between wall motion abnormalities and scintigraphic defects was low (58%). The additional value of exercise echocardiography and 201Tl SPECT to exercise test was greatest in patients with one-vessel disease. Thus, 1 month after an episode of unstable coronary artery disease in men, there is a high incidence of significant coronary stenoses as well as signs of ischemia shown both by wall motion abnormalities during exercise echocardiography and by postexercise studies with 201Tl SPECT. Exercise echocardiography gives a higher diagnostic yield regarding occurrence of reversible ischemia.

Ambulatory ST-recording has no additional value to exercise test for identification of severe coronary lesions after an episode of unstable coronary artery disease in men.

One month after an episode of unstable coronary artery disease, 95 male patients performed coronary angiography, 48 hours ambulatory ST-recording and also an exercise test. ST-depression occurred in 29.5% during the ST-recording and in 44.2% during the exercise test (p < 0.05). In patients with ST-depression at ambulatory monitoring, 79% demonstrated the same finding at the exercise test. A high risk response at the exercise test--defined as either ST-depression in > or = 3 leads, ST-depression in 1-2 leads with a maximal work load below the 60th percentile or a maximal work load below the 30th percentile regardless of the ECG reaction--occurred in 56.8%. Severe coronary lesions--defined as three vessel disease, left main stenosis or proximal left anterior descending artery stenosis as part of two vessel disease--was observed in 46.3%. Patients with a high risk exercise test response and patients with ST-depression during ST-recording had severe coronary lesions in 67% and 64% respectively. However, a high risk exercise test response occurred in 82%, while ST-depression at ambulatory monitoring was observed only in 41% of the patients with severe coronary lesions (p < 0.001). Thus, ambulatory ST-recording one month after an episode of unstable coronary artery disease in men adds no further information to a symptom limited exercise test in order to identify patients with severe coronary lesions.

Exercise echocardiography: a methodological study comparing peak-exercise and post-exercise image information.

It is unclear whether echocardiography at peak bicycle exercise adds information to registrations obtained recumbent immediately after the test and what factors influence image quality. Therefore, exercise echocardiography was performed consecutively and prospectively in 66 men, unselected with regard to echocardiography, one month after an episode of unstable coronary artery disease. Of 594 segments (9 x 66), 569 (96%) were adequately visualized recumbent at rest. The corresponding figures recumbent directly after exercise, seated before exercise, and seated at peak exercise were 544 (92%), 474 (80%), and 428 (72%), respectively. In the majority of our patients, acceptable images at peak exercise were obtained for the septal region, while for the anterior, lateral, and inferior segments the success rate varied from 50 to 70%. Recumbent after exercise, the success rate was acceptable for most segments, possibly with the exception of the apical and lateral segments. Fifty-five patients developed new wall motion abnormalities or worsening of wall motion in connection with exercise. Echocardiography at peak exercise provided more information than afterwards in patients with images of good quality. However, in patients with inferior image quality, the registrations obtained recumbent after the test revealed wall motion abnormalities which were not obtained seated at peak exercise. Patients with worse image quality had significantly higher respiratory rate and weight, and rated a higher degree of dyspnoea at peak exercise than those with good quality. We conclude that in middle aged men with coronary artery disease, image acquisition at peak bicycle exercise and immediately after exercise are of complementary value.