Reflux through Normal Aortic Valves

Fabian, Carl E.; Abrams, Herbert L.

doi:10.1097/00004424-196805000-00006

Cited by 11 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 'closing whiff' described in this paper should not be considered as incompetence, and some authors have even speculated that this is a normal phenomenon (Littmann, Dean, Crowley, Gilson, and Williams, 1961 ;Criley, 1968;Fabian and Abrams, 1968). It might be argued that any aortic root injection creates an abnormal situation, and that our method of injection, using a catheter with open end hole, might produce artefactual incompetence.…”

Section: Discussionmentioning

confidence: 80%

Radiology of homograft aortic valves

Brandt

Roche

Barratt‐Boyes

1969

Thorax

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 80%

Radiology of homograft aortic valves

Brandt

Roche

Barratt‐Boyes

1969

Thorax

View full text Add to dashboard Cite

“…Nelson et al (11) emphasized competency of the normal aortic valve in dogs when a closed-tip catheter was used for injection in aortic angiography. However, Fabian and Abrams (12) found aortic reflux in 35% of 190 contrast injections into the aorta in normal dogs. The incidence of regurgitation increased with increasing injection rates and intrabronchial pressure.…”

mentioning

confidence: 97%

Effects of Variations in the Strength of Left Ventricular Contraction on Aortic Valve Closure in the Dog

Bernuth

Tsakiris

Wood

1971

Circulation Research

View full text Add to dashboard Cite

The efficiency of aortic valve closure was studied in five experiments on three normal dogs by simultaneous roentgen videodensitometry, upstream sampling of dye dilution and recording of flow velocity and direction in the ascending aorta using a chronically implanted electromagnetic flowmeter. The aortic valve closed effectively during regular ventricular contractions. However, aortic reflux was observed whenever a weak ventricular contraction produced an opening of the aortic valve that was barely detectable, as evidenced by a minimal aortic pressure pulse and stroke volume. This type of aortic regurgitation was mild and invariably occurred at the end of ventricular ejection, coincident with the aortic incisura. Such regurgitation may be clinically significant in some instances of bigeminal rhythm or rapid atrial fibrillation, and is especially important for the evaluation of aortic angiograms. It further supports the concept that competent aortic valve closure depends on vortex formation in the sinus of Valsalva of sufficient degree to keep the aortic valve leaflets in partial apposition during ejection of blood from the ventricle across the aortic valve. KEY WORDScardiac arrhythmias and aortic valve closure stroke volume aortic flow and pressure pulses regurgitation across normal aortic valve mechanism of aortic valve closure electromagnetic flowmeter roentgen videodensitometry• The normal aortic valve works so efficiently that no appreciable amount of blood is regurgitated. Recently, however, reproducible mild aortic reflux was observed after weak ventricular beats in the course of experiments on normal dogs (1). In the present study, aortic reflux after weak ventricular contractions in normal dogs was analyzed systematically, and the implications for the understanding of the mechanism of normal aortic valve closure are discussed. Material and MethodsFive experiments were made on three normal mongrel dogs weighing 14 to 18.5 kg. A cuff type From Mayo Graduate School of Medicine (University of Minnesota), Rochester, Minnesota. of electromagnetic flow transducer was implanted around the ascending aorta 3 to 12 weeks before the experiments. Also, to carry out studies at slow heart rates, complete heart block was produced by a percutaneous technique (2).During the experiments, the dogs were anesthetized with initial injections of morphine, 2.5 mg/kg im, and pentobarbital, 15 mg/kg iv; pentobarbital was given as necessary to maintain light anesthesia. Heart rate and temporal sequence of atrial and ventricular contractions were controlled by bipolar electrode catheters positioned against the wall of the right atrium and the outflow tract of the right ventricle and connected to coupled electronic pacemakers. A 6-F Lehman catheter was placed in the main pulmonary artery and used for injections of indocyanine green for measurement of cardiac output. Additional 5-F or 6-F Lehman catheters with their tips positioned in the aortic arch or thoracic aorta, femoral artery, and transseptally into the left atrium and ventricl...

show abstract