PubMed HealthSearch

PubMed · 1627864

Mitral and aortic valvular flow: quantification with MR phase mapping.

Abstract

When magnetic resonance phase mapping is used to quantitate valvular blood flow, the presence of higher-order-motion terms may cause a loss of phase information. To overcome this problem, a sequence with reduced encoding for higher-order motion was used, achieved by decreasing the duration of the flow-encoding gradient to 2.2 msec. Tested on a flow phantom simulating a severe valvular stenosis, the sequence was found to be robust for higher-order motion within the clinical velocity range. In eight healthy volunteers, mitral and aortic volume flow rates and peak velocities were quantified by means of phase mapping and compared with results of the indicator-dilution technique and Doppler echocardiography, respectively. Statistically significant correlations were found between phase mapping and the other two techniques. Similar studies in patients with valvular disease indicate that phase mapping is also valid for pathologic conditions. Phase mapping may be used as a noninvasive clinical tool for flow quantification in heart valve disease.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

L Søndergaard, C Thomsen, F Ståhlberg, E Gymoese, K Lindvig, P Hildebrandt, O Henriksen. Mitral and aortic valvular flow: quantification with MR phase mapping.. https://doi.org/10.1002/jmri.1880020308

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Transcatheter umbrella closure of valvular and paravalvular leaks.

OBJECTIVES: Our aim was to adapt the technique of transcatheter umbrella closure of intracardiac defects for closure of valvular and paravalvular defects. BACKGROUND: The double-umbrella device developed by Rashkind and Cuaso has been safely and effectively delivered across a host of intracardiac defects, but transcatheter closure of valvular and paravalvular leaks has not been reported. METHODS: Between February 1987 and September 1990, eight patients who were believed to be poor operative candidates were taken to the catheterization laboratory for transcatheter double-umbrella closure of a valvular or a paravalvular leak. Four patients had a paravalvular leak around a prosthetic aortic valve. The other four patients had a valvular leak: one patient with a regurgitant native aortic valve after a Stansel procedure and three patients with a regurgitant porcine valve in a left ventricular apex to descending aorta conduit. RESULTS: Placement of a double-umbrella device was attempted in seven of the eight patients and was successful in all seven. Device placement was not attempted in one patient because of the crescentic shape of his defect. Two patients required two devices for each closure; the other five required only one device each. Angiography, performed on six patients after device closure, demonstrated that three patients had a completely occluded defect, two had trivial residual flow and one patient had mild residual flow through the device. All significant complications occurred in one patient who had hemolysis and oliguria that resolved when the initial umbrella was replaced by a larger device. In addition, two devices migrated to the patient's pulmonary arteries but were retrieved in the catheterization laboratory without difficulty. No other early or late complications occurred in 21 to 50 months of follow-up. Of the four patients with a paravalvular leak, the one who did not receive a device died at operation, one patient died at operation for an associated defect (in the operating room the umbrella was found securely in place across the paraaortic defect) and two patients are clinically well at home after 21 and 32 months, respectively. Of the four patients with closure of a valvular leak, one patient remains well at home 50 months later, one patient died at operation for associated defects and two patients had additional successful surgical treatment and remain well 29 months after device placement. CONCLUSIONS: Transcatheter umbrella closure appears to be a reasonable alternative for closure of a valvular or paravalvular leak in patients who are poor operative candidates.

Aortic Valve

[Results of heart valve replacement. Prognosis--occupational and general disability--occupational rehabilitation].

The success of valve surgery has led to a marked improvement in prognosis, quality of life and exercise tolerance in patients with symptomatic valvular heart disease. The degree of subjective and objective improvement depends on multiple preoperative factors like NYHA status, left ventricular function, valve lesion and type of valve replaced as well as peri- and postoperative factors like the occurrence of a perioperative myocardial infarction, the degree of intraoperative myocardial damage, the type of valve replaced and the speed and degree of postoperative regression of left ventricular hypertrophy and dilatation. The postoperative exercise tolerance is a major determinant for postoperative vocational rehabilitation. Therefore the individual functional assessment of patients postoperatively is of major importance.

Aortic Valve