Real-time myocardial contrast dobutamine stress echocardiography in coronary stenosis.

Background: Simultaneous wall motion and myocardial perfusion analysis could offer advantages over either method alone. Diagnostic utility of combining these parameters during dobutamine stress echocardiography is evaluated in this study.

Methods: Myocardial contrast dobutamine stress echocardiography was performed on thirty-eight patients with single or double vessel coronary artery stenosis of >50%.

A case of spontaneous coronary artery disease regression.

Coronary angiographic trials have demonstrated that lowering cholesterol can slow the progression of atherosclerosis, limit the formation of new lesions and enhance atherosclerotic regression together with reducing the incidence of clinical events (Waters D, 1996). Spontaneous regression of coronary atherosclerotic lesions is rare. We report the case of a patient with a severe within-stent restenotic lesion whose coronary disease spontaneously regressed 12 months after initial diagnosis, allowing for medical treatment of symptoms rather than repeated intervention.

Treatment of iatrogenic aortic dissection by percutaneous stent placement.

During elective cardiac catheterization via the right femoral artery, difficulty was encountered advancing the guidewire beyond the aortic arch and the procedure abandoned. The patient later developed back pain and hypotension. A contrast-enhanced spiral computed tomography scan confirmed aortic dissection, extending from an entry point in the external iliac artery to the arch.

Prognostic value of stress echocardiography in women with high (> or = 80%) probability of coronary artery disease.

Objective: To assess the prognostic significance of stress echocardiography in women with a high probability of coronary artery disease (CAD).

Setting: Secondary and tertiary cardiology unit at a university teaching hospital.

Participants: A total of 135 women (mean (SD) age 63 (9) years) with pre-test probability of CAD > or = 80% were selected from a database of patients investigated by treadmill or dobutamine stress echocardiography between 1995 and 1998.

Prognostic value of negative dobutamine stress echo in women with intermediate probability of coronary artery disease.

Women with an intermediate pretest probability of coronary artery disease represent a significant proportion of patients referred for the investigation of chest pain. Dobutamine stress echocardiography can be used to restratify these patients into a low-risk group without resorting to cardiac catheterization.

Computer-generated attenuation correction does not improve the accuracy of myocardial perfusion scintigraphy.

A short study was performed to determine if it is possible to increase the accuracy of thallium-201 (201T1) single photon emission tomographic myocardial perfusion imaging using computer-generated ('Chang') attenuation correction. The stress and rest myocardial perfusion studies from 22 patients with suspected or known ischaemic heart disease were reconstructed with and without "Chang' attenuation correction. For all patients, the scintigraphy results were compared with those of coronary angiography.

Anterior ST segment elevation due to isolated right ventricular infarction during right coronary angioplasty.

We describe the case of a 59-year-old man who developed anterior ST segment elevation and Q waves due to isolated right ventricular branch occlusion during right coronary angioplasty. Isolated right ventricular infarction was clearly demonstrated on echocardiography.

Reduction of mismatch of global ventilation and perfusion on exercise is related to exercise capacity in chronic heart failure.

Background: The inability to match lung perfusion to ventilation because of a reduced cardiac output on exercise contributes to reduced exercise capacity in chronic heart failure.

Objective: To quantify ventilation to perfusion matching at rest and at peak exercise in patients with chronic heart failure and relate this to haemodynamic and ventilatory variables of exercise capacity.

Design: Eight men in New York Heart Association class II underwent maximal bicycle ergometry with expired gas analysis.

Inhaled bronchodilators increase maximum oxygen consumption in chronic left ventricular failure.

Bronchoconstriction is seen at rest in patients with chronic heart failure, and may contribute towards exercise limitation. To investigate the effect of bronchodilator agents on exercise capacity, 10 patients (mean age 60 years, range 39-72) in New York Heart Association class II and III heart failure, underwent symptom-limited maximal exercise testing after inhalation of nebulized salbutamol (5 mg), ipratropium bromide (500 micrograms) or placebo delivered on separate days in a randomized, double-blinded study. There was an increase in forced expiratory volume in one second from pre-treatment to after nebulizer, 2.

Short-stepping gait in severe heart failure.

Background: Patients with severe chronic heart failure seem to take shorter steps than healthy controls when walking on a treadmill and when walking freely along a corridor. In healthy individuals the pattern of walking affects the oxygen cost of exercise, and so this observation might be relevant to the limitation of exercise in heart failure.

Method: Length of stride was analysed as stride/stature index in 15 controls, 10 patients with moderate heart failure, 10 patients with severe heart failure, and 10 patients with angina, walking at a constant speed/stature index.

Reduced pulmonary microvascular permeability in severe chronic left heart failure.

Pulmonary edema is a serious complication of heart failure, but often patients with chronic heart failure resist pulmonary edema despite elevated pulmonary venous pressures. This protection might be a result of decreased pulmonary microvascular permeability. Double-isotope scintigraphy with 113mindium-labeled transferrin and 99mtechnetium-labeled erythrocytes allows noninvasive estimation of pulmonary microvascular permeability; an index of transferrin accumulation is calculated that reflects microvascular permeability.

Use of limb movement sensors as indicators of the level of everyday physical activity in chronic congestive heart failure.

The level of everyday physical activity of patients with chronic congestive heart failure (CHF) may be an important reflection of their quality of life. Everyday physical activity is difficult to measure objectively, and may not relate to exercise capacity determined by laboratory exercise testing. A light-weight sensor worn on the wrist or ankle, which provides a cumulative record of limb movement, was evaluated.

Exercise physiology and the role of the periphery in cardiac failure.

Cardiopulmonary exercise testing remains the standard method of functional assessment in chronic heart failure, and both peak oxygen consumption achieved on progressive maximal exercise testing and anaerobic threshold are widely used endpoints in clinical trials. Peak oxygen consumption achieved on progressive maximal exercise testing may be used in clinical practice to estimate prognosis and aid the prioritization of patients for cardiac transplantation. Anaerobic threshold is a valuable index of submaximal exercise performance, but there are many different criteria used to define anaerobic threshold and careful attention to the methodology is essential.

Abnormal diastolic filling patterns in chronic heart failure--relationship to exercise capacity.

Abnormal patterns of diastolic ventricular filling are well recognized in chronic heart failure, but their relationship to the severity of heart failure is not known. The present study evaluates the relationship of diastolic filling indices to the severity of heart failure and to exercise capacity. In 40 patients with chronic heart failure secondary to ischaemic left ventricular impairment, exercise capacity was measured as peak oxygen consumption (VO2max) by progressive treadmill exercise.

Effects of amiodarone on erect and supine exercise haemodynamics and exercise capacity in patients with hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a primary heart muscle disease associated with a high incidence of sudden death. Amiodarone is of benefit in those patients with a high risk profile for sudden death. Amiodarone has also been reported to improve symptoms dramatically in some patients with HCM but to cause functional deterioration in others.

Pseudo preexcitation syndrome.

During the course of investigation for palpitations, a 62-year-old man underwent exercise testing using a MARQUETTE CASE 12 computerized exercise testing system. By stage III of the modified Bruce protocol, the computer-generated electrocardiogram appeared to show the development of exercise-induced preexcitation. Closer examination of the raw unfiltered data showed this to be a computer-generated artifact rather than true preexcitation.

A critical threshold of exercise capacity in the ventilatory response to exercise in heart failure.

During exercise patients with chronic left heart failure ventilate more than normal individuals at the same workload; the ratio of minute ventilation to minute production of carbon dioxide (VE/VCO2) is increased. The relation between increased VE/VCO2, severity of heart failure, and exercise capacity has not been defined. VE/VCO2 was measured in 47 patients with chronic left heart failure (New York Heart Association grades II and III) and in 1009 healthy controls.