sodium-pertechnetate-tc-99m and Aortic-Valve-Stenosis

Radionuclide measurements of ejection fraction were used to assess immediate and late postoperative ventricular function after the use of either a pulmonary artery vent (group A) or a left ventricular vent (group B) in 20 patients undergoing aortic valve replacement for pure aortic stenosis. Ten patients were included in each group and anesthetic techniques, patient management, and septal temperatures were similar in all cases. No significant difference was found between the preoperative and immediate or 6-week postoperative ejection fractions, either taken overall or between the two groups (p greater than 0.05; Student's t test). No correlation was found between cross-clamp time, bypass time, or the occurrence of ventricular fibrillation and the immediate postoperative ejection fraction (p greater than 0.05; Student's t test). There was no significant difference in the incidence of ventricular fibrillation after each type of vent had been used (chi 1(0) = 3.32; p greater than 0.05). We did not demonstrate any abnormalities in regional wall motion associated with apical insertion of a left ventricular vent, and conclude that pulmonary artery and left ventricular vents are equally satisfactory in terms of postoperative ventricular performance.

Topics: Adult; Aged; Aged, 80 and over; Aortic Valve Stenosis; Catheterization; Female; Heart; Humans; Male; Middle Aged; Myocardial Contraction; Postoperative Complications; Pulmonary Artery; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume

This is an account of 2 groups of 10 patients each who received Starr Edwards ball valves in either the mitral (M) or aortic (A) position on average 14.7 +/- 3 or 14.9 +/- 2.4 years ago, respectively. Non-invasive scintigraphic studies were performed using the first pass of 18 to 20 mCi 99 m-Technetium Pertechnetate. Enddiastolic and endsystolic volumes were found elevated at rest: (M) EDV 135 +/- 50 ml, ESV 63 +/- 30 ml; (A) EDV 163 +/- 41 ml, ESV 69 +/- 25 ml. The response to maximum exercise--during which the heart rate increased from 85 +/- 23 min-1 to 133 +/- 33 min-1--was abnormal, since none of the volumes changed significantly. During exercise, therefore, the increase of the cardiac output was totally heart rate dependent: (M) 6.1 +/- 2.3 to 9.3 +/- 2.3 l/min; (A) 7.0 +/- 1.9 to 10.9 +/- 3.1 l/min. The dynamics of the rapid diastolic filling rate of the left ventricle (RFR) and the mean pulmonary transit time (MTT) served as functional parameters of the Starr Edwards ball valves in the mitral position. The rapid filling rate increased from 205 +/- 98 to 321 +/- 58 ml/sec, whereas MTT decreased from 7.4 +/- 1.4 to 5.4 +/- 2.1 sec. In patients with aortic valve replacement the left ventricular ejection rate was assessed, it rose from 233 +/- 80 to 459 +/- 232 ml/sec. The significant changes of the parameters proved that the Starr Edwards ball valve mechanism functions satisfactorily 11 to 19 years post-operatively.

Topics: Aortic Valve Insufficiency; Aortic Valve Stenosis; Cardiac Output; Exercise Test; Follow-Up Studies; Heart Failure; Heart Valve Prosthesis; Hemodynamics; Humans; Mitral Valve Insufficiency; Mitral Valve Stenosis; Radionuclide Imaging; Sodium Pertechnetate Tc 99m

Forty patients having aortic valve replacement were evaluated preoperatively for ventricular arrhythmia and left ventricular ejection fraction. Arrhythmias were classified as complex or simple using the Lown criteria on the 24-hour ambulatory electrocardiogram; ejection fractions were determined by radionuclide gated blood pool analysis and contrast angiography. The ejection fractions determined by radionuclide angiography were 59.1 +/- 13.1% for 26 patients with simple or no ventricular arrhythmias, and 43.9 +/- 20.3% for 14 patients with complex ventricular arrhythmias (p less than 0.01). Ejection fractions determined by angiography, available for 31 patients, were also lower in patients with complex ventricular arrhythmias (61.1 +/- 16.3% versus 51.4 +/- 13.4%; p less than 0.05). Seven of 9 patients showing conduction abnormalities on the electrocardiogram had complex ventricular arrhythmias. Eight of 20 patients with aortic stenosis had complex ventricular arrhythmias, while 2 of 13 patients with aortic insufficiency had such arrhythmias. It is concluded that decreased left ventricular ejection fraction, intraventricular conduction abnormalities, and aortic stenosis are associated with an increased frequency of complex ventricular arrhythmias in patients with aortic valve disease.

Topics: Aortic Valve; Aortic Valve Insufficiency; Aortic Valve Stenosis; Arrhythmias, Cardiac; Coronary Angiography; Electrocardiography; Female; Heart; Heart Valve Prosthesis; Heart Ventricles; Hemodynamics; Humans; Male; Middle Aged; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Technetium

First pass radionuclide angiocardiography was utilized to calculate right and left ventricular ejection fraction in 74 infants and children. For the synchronization of radionuclide imaging with the cardiac cycle, the peaks and valleys of corrected ventricular time activity curve were adopted as the time reference points instead of R wave of electrocardiogram. Left ventricular ejection fractions obtained by the radionuclide technique correlated well with those derived from the contrast angiographic technique (r = 0.90), but right ventricular ejection fractions correlated less well (r = 0.74). This noninvasive technique appeared useful for evaluation of right and left ventricular ejection fraction.

Topics: Aortic Valve Insufficiency; Aortic Valve Stenosis; Cardiac Output; Cardiomyopathies; Child; Child, Preschool; Female; Heart Defects, Congenital; Heart Diseases; Humans; Infant; Male; Mitral Valve Insufficiency; Mucocutaneous Lymph Node Syndrome; Pulmonary Valve Insufficiency; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Stroke Volume; Syndrome; Technetium