Stefan P. Karwatowski

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OBJECTIVES This study investigated whether combining exercise with adenosine would reduce the adverse effects of adenosine vasodilation. BACKGROUND Adenosine vasodilation is effective for perfusion imaging but causes frequent unpleasant noncardiac adverse effects, high noncardiac tracer uptake and occasional arrhythmias. METHODS Of 500 consecutive(More)
PROBLEM Atrial fibrillation is the most common persistent arrhythmia in adults and carries an increased risk of thromboembolism and stroke. Electrical (DC) cardioversion is an effective treatment, but logistical difficulties in many institutions lead to problems providing a prompt service. This reduces the rate of long term success, delays relief of(More)
Abnormal diastolic left ventricular function is an early marker for myocardial disease and may be impaired even when global systolic function is normal. Subendocardial function is affected early in ischaemic heart disease and by altering left ventricular long axis motion, may contribute to abnormal transmitral pressure gradients. Regional myocardial long(More)
The aim of this study was to assess the effect of scleroderma on left ventricular mass and subendocardial function using cardiovascular magnetic resonance (CMR) to determine parameters reflecting early dysfunction from fibrosis. Fifteen patients with a history of scleroderma had left ventricular mass measured with standard techniques and regional(More)
Diastolic function is an important element of overall left ventricular function. The pattern of flow across the mitral valve is commonly used as a measure of diastolic ventricular function. Magnetic resonance (MR) velocity mapping of blood flow across the mitral valve was compared with Doppler echocardiography. Nineteen patients with known coronary artery(More)
A motion-registered spatiotemporal phase-unwrapping method for extending the dynamic range of cine magnetic resonance phase velocity measurements is presented. The interframe cardiac movement is estimated from the magnitude image derived from the velocity encoded raw data, which ensures that the phase signal is unwrapped in the temporal direction with(More)
To date cardiac positron emission tomography (PET) studies have focussed on the measurement of myocardial blood flow, metabolism and receptors while left ventricular (LV) function and dimensions have been derived from other modalities. The main drawback of this approach is the difficulty of data co-registration, which limits clinical interpretation. The aim(More)
OBJECTIVE To assess the pattern of global and regional left ventricular long axis motion during early diastole in patients with ischaemic heart disease with and without myocardial infarction using magnetic resonance velocity mapping. DESIGN Prospective study of 26 patients with a history of myocardial infarction (age 29-78, mean 55 years) and 21 patients(More)
Magnetic resonance (MR) imaging provides an accurate measurement of left ventricular mass but imaging time can be up to 45 min. We tested a more rapid multislice spin echo technique on 16 volunteers without evidence of heart disease. Multislice short axis spin echo images were acquired in up to three sets of five, clustered around end systole. Total imaging(More)