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J A Bianco

Publications and source records attributed to J A Bianco.

11 recordsLinked to original sources
PubMed1979

Assessment of left ventricular function in aortic insufficiency using echocardiography, gated scintigraphy and contrast angiography.

Echocardiography, gated scintigraphy and contrast angiography were used to measure left ventricular ejection fractions in 20 patients with varying degrees of aortic insufficiency. There was good correlation between the radionuclide and the angiographic ejection fractions. Echocardiographic ejection fraction correlated less well with the angiographic ejection fraction. The radionuclide left ventricular ejection fraction may prove valuable in the noninvasive serial evaluation of left ventricular function in patients with chronic aortic insufficiency.

Adult↗
PubMed1979

Abnormal images of right heart disorders.

Increasing attention is being given to radioisotopic studies of the right heart. Measurement of right ventricular ejection fraction has become more common. We present examples of cardiac images which were obtained during the scintigraphic assessment of right sided cardiac disorders. Images of the first pass, of the gated cardiac study, and of the nongated cardiac blood pools offer complementary information to the overall radionuclide evaluation of right heart disease.

Blood Pressure↗
PubMed1979

Radionuclide left ventricular dV/dt for the assessment of cardiac function in patients with coronary disease.

To investigate potential uses of left-ventricular (LV) systolic ejection rate (LV dV/dt) in the evaluation of LV function, we examined the effect of exercise, angiotensin, and leg raising on LV ejection fraction and LV dV/dt in patients with coronary-artery disease. The following observations were made: a) LV ejection fraction and dV/dt changed proportionately, but in opposite directions, during supine exercise; b) LV ejection fraction and dV/dt decreased to a similar extent during angiotensin infusions; and c) LV ejection fraction and dV/dt were unchanged by leg raising. The changes in peak and mean LV dV/dt were similar. Regardless of the physiologic state, peak LV dV/dt occurred during the first third of systole. These data imply that in this population there were no specific advantages of LV dV/dt over LV ejection fraction in the evaluation of LV performance.

Angiotensin II↗
PubMed1978

Implications of liver activity associated with 133Xe ventilation lung scans.

A series of 35 xenon-133 (133Xe) ventilation studies yielded nine cases demonstrating accumulation of activity in the liver. Maximum intrahepatic deposition of radioxenon occurred during the washout phase of the study. In addition to those clinical instances which make this phenomenon possible, i.e., obesity, alcoholic-induced liver steatosis and diabetes mellitus, we found that hyperlipidemia and coronary artery disease also favor xenon-133 localization into the hepatic parenchyma. It is concluded that the lipid avidity of 133Xe facilitates its liver accumulation hyperlipidemic patients and in patients with coronary artery disease, and that this action may be explored to further understand deranged metabolic pathways in the liver of these patients. Hepatic accumulation of 133Xe during ventilation studies must be considered when assessing regional ventilation/perfusion relationships.

Adult↗
PubMed1977

Effect of sodium bicarbonate on canine left ventricular function.

Left ventricular performance was evaluated in seven canine right heart bypass preparations during and after the intraauricular administration of sodium bicarbonate (100 ml, 1100 Osm, 60 mEq). Under conditions of constant cardiac input and left ventricular volume, sodium bicarbonate produced mild and brief left ventricular depression, as manifested by a decline of left ventricular dp/dt with simultaneous rise of left ventricular end-diastrolic and left atrial pressures. These findings occurred as aortic impedance fell. Identical results accrued in paced and unpaced preparations. The data lends credence to the proposition that a sudden rise in blood pCO2 produces increased transport of CO2 across the cardiac membranes with intracellular acidosis. However, the data is also compatible with hyperosmolality induced contractile depression. Possible clinical implications are discussed.

Animals↗
PubMed1976

Effects of ketamine on canine cardiovascular function.

Left ventricular contractility was assessed before and during the peak effect of ketamine in eight canine right heart bypass preparations. Myocardial contractility was defined in terms of maximum left ventricular dp/dt, the ejection fraction, and left ventricular end-diastolic and left atrial pressures at constant heart rate and cardiac inflow. Ketamine produced significant decreases in contractility and there were some indications of a dose-response pattern. The action of ketamine was dependent partly on changes in arterial pressure, as the drug caused a mild but sustained vasodilatation which was not dose-dependent. These data offer further evidence of a small and transient negative inotropic effect of ketamine.

Animals↗
PubMedDate not supplied

Radionuclide methods in the assessment of left ventricular function.

The recent introduction of newer scintillation cameras, convenient radiopharmaceuticals and innovative data-processing systems has hastened the use of radionuclide methods in the evaluation of cardiac function. This review familiarizes the primary internist with physics and instrumentation required in understanding cardiovascular nuclear images. Basic principles underlying the gated cardiac blood-pool scan and the first-pass study are described. Authoritative references are given to readers seeking more complete information. The major emphasis of the review, however, is on the clinical applications of these techniques. The role of these noninvasive methods in myocardial infarction, diagnosis and prognosis of ischemic heart disease, assessment of cardiomyopathies, study of idiopathic hypertrophic subaortic stenosis and left atrial myxoma is discussed. Finally, mention is made of newer applications: evaluation of nitroglycerin action on viable but ischemic myocardium and determination of the hemodynamic effects of propranolol in patients with coronary-artery disease.

Angiocardiography↗