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PubMed1999

Role of Contrast Echocardiography for the Assessment of Left Ventricular Function.

The endocardial border of the left ventricle is incompletely identified in at least 30% of patients at rest or during stress echocardiography during fundamental imaging. This may lead to inaccurate assessment of regional and global left ventricular function or may lead to further diagnostic imaging with another modality resulting in a higher cost of healthcare. The recent development of second generation ultrasound contrast agents has resulted in improved detection of endocardial border at rest and during stress fundamental echocardiography. This has been consistently shown in various clinical trials involving 702 patients using a new contrast agent, SonoVuetrade mark. Other studies with contrast agents have also shown improved accuracy for determining left ventricular ejection fraction and volumes. Although unenhanced tissue harmonic imaging itself improved the assessment of left ventricular function, contrast enhanced harmonic imaging has recently been shown to be more accurate; however, larger clinical studies are required to establish the value of harmonic contrast imaging for the assessment of left ventricular function.

Journal Article↗

PubMed1994

Reduced lymphocyte beta 2-adrenoceptor density and impaired diastolic left ventricular function in patients with glucocorticoid deficiency.

OBJECTIVE: Patients with adrenal crisis are at risk of severe hypotension not responding to administration of catecholamines. As glucocorticoids may be a prerequisite for intact beta-adrenoceptor function, impaired adrenoceptor activity may explain the hypotension and reduced cardiac performance in adrenal insufficiency. The aim of our study was, therefore, to further elucidate the permissive action of glucocorticoids on adrenergic function and cardiac performance. DESIGN: Prospective randomized controlled study. PATIENTS: Nine patients with adrenal insufficiency were investigated before and 48 hours after glucocorticoid withdrawal. Mineralocorticoid therapy remained unchanged during the study period. MEASUREMENTS: Lymphocyte beta 2-adrenoceptor density, intracellular c-AMP response to isoprenaline, platelet alpha 2-receptor density, plasma catecholamines, serum cortisol, plasma ACTH, echocardiography. RESULTS: Glucocorticoid depletion was demonstrated by a fall in serum cortisol from mean +/- SEM 441 +/- 62 to 45 +/- 18 nmol/l. Glucocorticoid withdrawal decreased lymphocyte beta 2-receptor density from 798 +/- 111 to 498 +/- 54 binding sites/cell (P < 0.05) and the intracellular c-AMP response to isoprenaline from 15.0 +/- 4.2 to 8.2 +/- 1.7 pmol/10(6) cells (P < 0.05). Echocardiography showed impaired diastolic relaxation after glucocorticoid withdrawal with prolongation of the rapid filling period (80.3 +/- 12.5 vs 138.3 +/- 11.8 ms, P < 0.05). Plasma catecholamines, platelet alpha 2-receptor density and systolic left ventricular function were not affected by glucocorticoid deficiency. CONCLUSIONS: This study demonstrates the importance of normal glucocorticoid levels for beta 2-adrenoceptor function and helps to explain the decreased responsiveness to catecholamines and the impaired cardiac performance in adrenal crisis.

Adolescent↗

PubMed2005

Sympathetic denervation and reinnervation after the maze procedure.

UNLABELLED: We evaluated serial changes in cardiac sympathetic nerve distribution using 123I-metaiodobenzylguanidine (123I-MIBG) after the Maze procedure. The Maze procedure, in which multiple incisions are made in the atrium, has been concomitantly performed with mitral valve (MV) surgery in an attempt to eliminate atrial fibrillation (AF). Although attenuation of the sinoatrial node response to exercise and a reduction of left ventricular function (left ventricular ejection fraction [LVEF]) in early stages after the Maze procedure have been suggested, factors leading to these changes have not been clarified. METHODS: Thirteen patients with MV disease were enrolled in this study. Six of them had undergone MV surgery and the Maze procedure (Maze+), and 7 had undergone MV surgery without the Maze procedure (Maze-). All patients underwent cardiac 123I-MIBG imaging preoperatively and 10 d and 1 y after surgery to assess 123I-MIBG uptake (heart-to-mediastinum count ratio of early planar images [H/M]) and the washout rate (WR). Radionuclide ventriculography was also performed to calculate LVEF 3 d after each 123I-MIBG imaging. RESULTS: The LVEF of the Maze+ group significantly decreased 10 d after surgery (44.2 +/- 4.8; mean +/- SD) compared with that before surgery (60.3 +/- 6.9; P < 0.05) and significantly increased at 1 y (65.2 +/- 2.9) compared with that at 10 d (P < 0.05). In the Maze- group, there was no significant change 10 d (53.0 +/- 12.3) and 1 y (58.6 +/- 4.8) after surgery compared with that before surgery (60.4 +/- 4.6) (P = not significant, each). In the Maze+ group, the H/M (1.51 +/- 0.18) was significantly lower at 10 d after than that at the preoperative stage (1.90 +/- 0.25; P < 0.05) but significantly recovered at 1 y (2.23 +/- 0.18; P < 0.05) with a similar transient increase in the WR (36.7% +/- 6.1% at preoperative stage; 46.9% +/- 3.4% at 10 d; 39.9% +/- 6.5% at 1 y; P < 0.05, each). On the other hand, the Maze- group did not show a significant change in the H/M (1.94 +/- 0.32, 2.06 +/- 0.18, and 2.13 +/- 0.17, respectively; P = not significant, each) but did exhibit a significant decrease in the WR (40.4% +/- 5.1%, 37.0% +/- 5.1%, and 32.9% +/- 2.5%, respectively; P < 0.05, each). Changes in the H/M of both groups significantly correlated with the change in LVEF (r = 0.82; P < 0.05), and the WR showed a significant inverse correlation with changes in the LVEF (r = -0.81; P < 0.05). CONCLUSION: Cardiac sympathetic nerves were denervated at early stage and reinnervated at late stage after the Maze procedure. Such adrenergic nerve changes may be correlated, at least in part, with changes in left ventricular function after this procedure.

3-Iodobenzylguanidine↗

PubMed1980

Left ventricular function in cyanotic congenital heart disease.

Left ventricular function was studied with quantitative biplane cineangiocardiography in 39 preoperative and 23 postoperative patients with cyanotic congenital heart disease. Diagnoses included pulmonary atresia or critical pulmonary stenosis with intact ventricular septum (group 1), tricuspid atresia (group 2) and pulmonary atresia with ventricular septal defect (group 3). Preoperative patients ranged in age from 1 day to 7 years and postoperative patients from 7 weeks to 23 years. Left ventricular end-diastolic volume was increased in preoperative patients in groups 1 and 2 (132 and 136 percent of normal, respectively) but was normal in patients in group 3. Left ventricular ejection fraction was decreased to a similar extent in preoperative groups 1 to 3: 0.54, 0.55 and 0.56, respectively. After a shunt procedure left ventricular end-diastolic volume increased to 228 and 266 percent of normal in groups 1 and 2, respectively, but remained within normal limits in group 3. Left ventricular ejection fraction was normal in postoperative group 1 patients, whose ages averaged 1.8 years, but remained decreased in group 2 and 3 patients, whose ages averaged 8.1 and 5.6 years, respectively. Duration of cyanosis and degree of left ventricular dilatation appear to be important variables in regard to pump function in patients with cyanotic congenital heart disease.

Adolescent↗

PubMed1999

[Assessment of left ventricular function by 201Tl ECG-gated myocardial SPECT].

We applied the QGS program for LV function analysis (described by Germano, 1995) to a 201Tl SPECT study at rest, and estimated its accuracy. We performed 201Tl ECG-gated myocardial SPECT in 25 patients with ischemic heart disease under an acquisition time used in the routine 99mTc ECG-gated SPECT study. The quality of the gated images was visually assessed with a 4-point grading system. LVEDV, LVESV, LVEF determined by the QGS program were compared with those by Simpson's method on biplane LVG in 25 patients. Regional wall motion scores in 7 myocardial segments were assessed on the three-dimensional display created by the QGS program and the cine display of biplane LVG with a 5-point grading system. Wall motion scores obtained by the QGS program were compared with those by LVG. Although 72.0% of 201Tl ECG-gated SPECT images were fair or poor in image quality, there were good correlations between the values obtained by the QGS program and LVG (LVEDV: r = 0.82, LVESV: r = 0.88, LVEF: r = 0.89). In addition, wall motion scores by the QGS program were correspondent to those by LVG in 77.1% of all 175 myocardial segments. We conclude that the QGS program provides high accuracy in evaluating left ventricular function even from 201Tl ECG-gated myocardial SPECT data.

Aged↗

PubMed1978

[Changes in the subvalvular apparatus and left ventricular function in pure mitral stenosis].

Disordered left ventricular function and changes in the sub-valvular apparatus appear to be associated in patients with isolated mitral stenosis (MS). Left ventricular cine-angiography has demonstrated two groups of patients, according to the presence (group II) or absence (group I) of changes in the sub-valvular apparatus. There was no significant difference between the two groups in terms of age, heart rate, left ventricular end diastolic pressure, surface area of the mitral valve, or ventricular ejection time. However, group II patients had a lowered ejection fraction (EF), systolic ejection volume (SEB), speed of shortening of circular fibres (VCF), and systolic work index (SWI) compared with group I cases (respectively 0.49 +/- 0.06 and 0.58 +/- 0.04 for the EF, 36 +/- 7 ml.m-2 and 41 +/- 7 ml.m-2 for the SEV, 0.85 +/- 0.12 circ.s-1 and 1.09 +/- 0.16 circ.s-1 for the VCF, 45 +/- 11 gm.m-2 and 57 +/- 11 gm.m-2 for the SWI. Nevertheless, it appears that changes in the sub-valvular apparatus indicate rather than cause dysfunction of the left ventricle, which occurs in a certain number of patients who have a normal sub-valvular apparatus.

Adult↗

PubMedDate not supplied

Evaluation of left ventricular functions in chronic renal failure before and after acute hemodialysis.

Left ventricular functions were evaluated in 25 adult patients of chronic renal failure by 2-D echocardiography before and after four hours of standard hemodialysis session. Eighteen patients showed clinical evidence of fluid overload. Predialysis left ventricular end-diastolic diameter, left ventricular end-diastolic volume, left ventricular end-systolic diameter and left ventricular end-systolic volume were comparable in patients with or without fluid overload. Similarly, predialysis stroke volume and left ventricular ejection fraction were not significantly different in the two subsets. However, following hemodialysis there was a significant decrease in the left ventricular systolic and diastolic volumes and diameters in patients with fluid overload. The improvement in the left ventricular ejection fraction was of the same magnitude in the two subsets. The significant improvement in the left ventricular functions both in patients with and without fluid overload indicates that fluid overload may not be the only determinant of left ventricular functions in patients of chronic renal failure, but other factors, such as various uraemia toxins and metabolic changes might also be inhibiting the myocardial functions.

Adult↗

PubMed1996

Color-coded measures of myocardial velocity throughout the cardiac cycle by tissue Doppler imaging to quantify regional left ventricular function.

TDI is a new echocardiographic technique that calculates and displays color-coded myocardial velocity on-line. To determine the feasibility of endocardial velocity throughout the cardiac cycle as a means to quantify regional function, 20 normal subjects aged 30 +/- 5 years and 12 patients with heart disease aged 62 +/- 17 years were studied with a prototype TDI system. TDI M-mode images were acquired by using a multicolored velocity map (display range, -30 to 30 mm/sec; temporal resolution, 90 Hz). Color-coded velocity data were then converted to numeric values off-line at 50 msec intervals. Posterior wall velocities throughout the cardiac cycle by TDI were closely correlated with velocity calculations from the first derivative of routine digitized M-mode tracings (group mean r = 0.88 +/- 0.03, SEE = 7.0 +/- 1.1 mm/sec). Anteroseptal TDI color-coded systolic velocity occurred 164 +/- 84 msec from the onset of the electrocardiographic QRS compared with 203 +/- 33 msec in the posterior wall (P < 0.05) in normal subjects, consistent with normal electrical activation. Significant differences in systolic and diastolic posterior wall TDI velocity data were observed in patients with hypokinetic or akinetic segments assessed by independent routine study when compared with normal controls. Calculated systolic and early diastolic posterior wall TDI indexes correlated significantly with percentage of wall thickening. Of abnormal anteroseptal segments, TDI systolic time velocity integrals were significantly different than normal and correlated with percentage of wall thickening. TDI has potential to quantitatively assess regional left ventricular function.

Adult↗

PubMed2000

Echocardiographic evaluation of left ventricular function in pure mitral stenosis.

Echocardiographic evaluation of left ventricular function was performed in 22 cases of pure rheumatic mitral stenosis and 22 age matched normal persons. Cases with any evidence of rheumatic activity in the preceding six months, those with gross tricuspid regurgitation and paradoxical movement of the interventricular septum and cases with atrial fibrillation were excluded. None of the patients showed systolic left ventricular dysfunction. Left ventricular end diastolic dimension was also not affected. Echocardiographic parameters did not have any relation for mitral valve area. Our observations show that mitral stenosis per se does not affect left ventricular function.

Adolescent↗

PubMed2004

[Reproducibility of measurements of left ventricular function with gated myocardial perfusion SPECT and comparison with blood pool radionuclide ventriculography].

INTRODUCTION AND OBJECTIVE: This study was designed to evaluate the reproducibility of ejection fraction (EF) and ventricular volume measurements obtained with single photon emission computed tomography (gated-SPECT), and to assess the correlation between EF values obtained with this method and blood pool planar radionuclide ventriculography. PATIENTS AND METHOD: A total of 55 patients were included (37 men, mean age 61.3 years) upon referral to two nuclear cardiology units for diagnosis (50%) or follow-up of known coronary artery disease. In a standard 2-day protocol, patients received a dose of [99mTc]tetrofosmin (800 MBq) at stress and at rest. Two resting gated-SPECT studies were performed. QGS software was used to obtain left ventricular EF, end-diastolic volume (EDV) and end-systolic volume (ESV). Forty-nine patients agreed to undergo blood pool ventriculography on the third day. RESULTS: Interobserver variability was 0.5 (2.6)% (r=0.99) for EF, 1.9 (10.7) mL for EDV (r=0.98) and 0.5 (5.4) mL for ESV (r=0.99). Interassay variability was 2 (5.1)% (r=0.94) for EF, 4.5 (8.6) mL for EDV (r=0.99) and 3.4 (6.6) mL for ESV (r=0.99). The correlation between gated-SPECT EF and blood pool EF was suboptimal (r=0.75, 95%CI, 0.59-0.85). CONCLUSIONS: There was excellent interobserver and interassay reproducibility for left ventricular functional parameters measured with gated-SPECT and QGS software, and this method can be used for serial evaluations of ventricular function. Although the correlation between values obtained with gated-SPECT and blood pool ventriculography was acceptable, the differences show that the two techniques cannot be considered equivalent.

Coronary Disease↗

PubMedDate not supplied

Anomalous origin of the left coronary artery from the pulmonary artery in a premature infant with preserved left ventricular function.

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare condition. The majority of cases present with impaired left ventricular function. We report on a premature infant who was diagnosed at a gestational age near term with ALCAPA during routine cardiac examination. The patient showed no signs of myocardial ischemia and is doing well after corrective surgery. This is the youngest patient reported with ALCAPA and preserved myocardial function.

Coronary Vessel Anomalies↗

PubMed1981

Left ventricular function in mitral valve prolapse: assessment with radionuclide cineangiography.

Abnormalities of left ventricular contraction in patients with mitral valve prolapse have suggested a myocardial factor in this disease. To determine systolic left ventricular function in mitral valve prolapse, technetium-99m gated equilibrium radionuclide cineangiography was performed in 47 patients with this diagnosis. In 39 patients without mitral regurgitation the average ejection fraction was normal at rest (average [+/- standard error of the mean] 57 +/- 3 percent, normal 57 +/- 1 percent, difference not significant) and exceeded the lower limits of normal in all but 1 patient, whose ejection fraction was 41 percent. However, ejection fraction during maximal exercise was lower for the group of patients with mitral prolapse without mitral regurgitation than for normal subjects (average 64 +/- 2 percent, normal 71 +/- 2 percent, p < 0.005). In eight patients with mitral prolapse and mitral regurgitation, the average ejection fraction was normal at rest but was diminished with exercise in comparison with both normal subjects and patients with mitral valve prolapse without mitral regurgitation. Chest pain, arrhythmia and the pattern or extent of mitral valve prolapse on echocardiography were not independently associated with impaired left ventricular functional reserve. We conclude that, although many patients with mitral valve prolapse have normal left ventricular function, there is a subgroup without mitral regurgitation in whom diminished left ventricular functional reserve is suggestive of a cardiomyopathic process.

Adolescent↗

PubMed1995

Quantitative echocardiographic assessment of left ventricular function in critically ill obstetric patients: a comparative study.

OBJECTIVE: Our purpose was to compare different echocardiographic methods to quantitate maternal ventricular function. STUDY DESIGN: Eleven critically ill obstetric patients requiring invasive monitoring and M-mode and two-dimensional Doppler echocardiographic studies were retrospectively studied. Ventricular volumes and ejection fraction derived from multiple methods were computed and compared with analysis of variance and Newman-Keuls tests. RESULTS: Two M-mode studies could not be analyzed. M-mode and two-dimensional estimates of stroke volume were similar to the previously validated Doppler stroke volume values of these 11 patients. End-diastolic volume estimates were similar. There was no difference in ejection fraction for the five different two-dimensional Doppler methods used (66%, 66%, 67%, 63%, and 63%). CONCLUSION: Left ventricular function is reliably calculated in pregnant women by a number of different echocardiographic techniques. The ability to combine echocardiographic techniques is helpful when any single method does not provide all of the information required.

Adolescent↗

PubMed1994

Effect on short-term prognosis and left ventricular function of angina pectoris prior to first Q-wave anterior wall acute myocardial infarction.

The prognostic significance of angina pectoris before the development of first Q-wave anterior wall acute myocardial infarction (AMI) was assessed in 153 patients. A total of 100 patients in this study had angina before Q-wave AMI, whereas 53 patients had no antecedent symptoms of angina. The presence of angina before AMI was associated with a lower incidence of complications including sustained ventricular tachycardia or fibrillation (7% vs 25%, p = 0.0022), pump failure (24% vs 47%, p = 0.0035), cardiac rupture (1% vs 17%, p = 0.0001), and a lower in-hospital mortality rate (11% vs 28%, p = 0.0067). The peak creatine phosphokinase activity was lower in patients with than without antecedent angina (1,727 +/- 1,238 vs 2,675 +/- 2,569 IU/liter, respectively, p = 0.023). There was no difference in the prevalence of multivessel coronary artery disease or the presence of collateral circulation between the 2 groups. Left ventriculography revealed a higher left ventricular ejection fraction (54 +/- 13% vs 46 +/- 11%, p = 0.034) and smaller left ventricular end-diastolic volumes (75 +/- 15 vs 86 +/- 18 ml/m2, p = 0.017) in patients with than without antecedent angina. These findings suggest that the presence of angina before AMI may be associated with a protective effect on left ventricular function during anterior wall AMI. Although the precise mechanisms underlying the beneficial effects are unknown, they may be related to the development of collateral channels or ischemic preconditioning.

Adult↗

PubMed2000

Congenital severe aortic stenosis with congestive heart failure in late childhood and adolescence: effect on left ventricular function after balloon valvuloplasty.

Left ventricular (LV) dysfunction with congestive heart failure (CHF) resulting from severe congenital aortic stenosis (AS) is a well-described condition in infancy, but it is rarely found in older children and adolescents. Aortic valve surgery in such cases may be associated with higher rates of morbidity and mortality. Aortic valve balloon dilatation (AVBD) is a viable alternative, but its effect on LV function has not been evaluated. We describe follow-up results of AVBD in 10 cases of severe congenital AS in older children and adolescents with CHF and LV dysfunction. The ages of these patients ranged from 5 to 18 yr (mean +/- SD: 10.8 +/- 4 yr), and nine were males. The follow-up period after AVBD ranged from 3 mo to 7 yr (mean +/- SD: 2.93 +/- 2.1 yr). Success was achieved in all cases, with no immediate complications. After valvuloplasty, the peak-to-peak systolic gradient declined from 74.7 +/- 30.8 to 33.9 +/- 18.2 mm Hg (P < 0.0001). The cardiac index increased slightly but significantly, from 1.9 +/- 0.27 to 2.2 +/- 0.5 L/min/m(2) (P < 0.015). Hemodynamic improvement was also confirmed by a significant decrease in mean pulmonary artery and pulmonary artery wedge pressures from 41.9 +/- 9 to 32.6 +/- 6.6 and from 25.5 +/- 2.9 to 19.3 +/- 3.4 mm Hg, respectively. The echocardiographically derived left ventricular ejection fraction (LVEF) improved from 21.6 +/- 5. 37% to 31 +/- 6.5% within 24 hr after AVBD, and it further improved in all cases on follow-up. Mean LVEF at last follow-up was 59.4 +/- 11.4%. The Doppler instantaneous peak systolic gradient (IPSG) increased from 37.3 +/- 18.8 to 64.8 +/- 30.7 mm Hg at late follow-up. Significant aortic regurgitation (AR) developed in 20% of patients. The Doppler IPSG across the aortic valve was > 60 mm Hg in five cases on follow-up. Two of these patients underwent another AVBD successfully 4 and 16 mo later, respectively. Aortic valve replacement was done in two patients, one for severe restenosis with mild AR 12 mo after AVBD and another for severe re-restenosis with moderate AR 21 mo after a second AVBD. Severe congenital AS can be associated with LV dysfunction and CHF in late childhood and adolescence. AVBD results in good palliation with improvement in LV function on follow-up.

Adolescent↗

PubMedDate not supplied

[Left ventricular function in pure mitral stenosis. Hemodynamic echocardiographic study].

We studied the left ventricular performance in 40 patients with pure mitral stenosis, using a M Mode Echocardiographic study. In 19% of the group the left ventricular function was abnormal, however, we were able to distinguish three subsets: small left ventricular dimension, normaland dilated. In the first two subsets, the cardiac performance was normal in almost all the patients (85%). In 15%, the left ventricular function was depressed, probably due to a restricting flow into the cavity, segmental atrophy and fibrosis caused by chronic mitral obstruction. In the last group (dilated left ventricle), the end-systolic dimension was abnormal in 71,4% of the patients. Our study suggests that the increased dimension of the left ventricle is accompanied by poor ventricular performance and represents an intrinsic trace of damage of the myocardium by the previous rheumatic carditis. The importance of detecting this last subset is emphasized due to the high incidence of impairment in left ventricular function. This detection could in some cases prevent the surgical treatment when this function is severely depressed.

Adolescent↗

PubMed1983

Visual versus computerised assessment of left ventricular function from cinéangiography.

Visual assessment of left ventricular function from cinéangiography was compared with computerised assessment in 48 randomly selected cinéangiograms. The parameters compared included end-diastolic volume, end-systolic volume, stroke volume, ejection fraction and left ventricular output. There was poor agreement between visual and calculated values for end-diastolic volume, stroke volume and left ventricular output, but good agreement for ejection fraction and moderately good agreement for end-systolic volumes. Absolute values are particularly difficult to assess.

Cardiac Output↗

PubMed1983

Left ventricular function in chronic aortic regurgitation.

Left ventricular performance was determined in 42 patients with moderate or severe aortic regurgitation during upright exercise by measuring left ventricular ejection fraction and volume with radionuclide ventriculography. Classification of the patients according to exercise tolerance showed that patients with normal exercise tolerance (greater than or equal to 7.0 minutes) had a significantly higher ejection fraction at rest (probability [p] = 0.02) and during exercise (p = 0.0002), higher cardiac index at exercise (p = 0.0008) and lower exercise end-systolic volume (p = 0.01) than did patients with limited exercise tolerance. Similar significant differences were noted in younger patients compared with older patients in ejection fraction at rest and exercise (both p = 0.001) and cardiac index at rest (p = 0.03) and exercise (p = 0.0005). The end-diastolic volume decreased during exercise in 60% of the patients. The patients with a decrease in volume were significantly younger and had better exercise tolerance and a larger end-diastolic volume at rest than did patients who showed an increase in volume. The mean corrected left ventricular end-diastolic radius/wall thickness ratio was significantly greater in patients with abnormal than in those with normal exercise reserve (mean +/- standard deviation 476 +/- 146 versus 377 +/- 92 mm Hg, p less than 0.05). Thus, in patients with chronic aortic regurgitation: 1) left ventricular systolic function during exercise was related to age, exercise tolerance and corrected left ventricular end-diastolic radius/wall thickness ratio, and 2) the end-diastolic volume decreased during exercise, especially in younger patients and patients with normal exercise tolerance or a large volume at rest.

Adolescent↗