Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Atrial Function, Left”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources
PubMed2000

Time course of left atrial mechanical recovery after linear lesions: normal sinus rhythm versus a chronic atrial fibrillation dog model.

INTRODUCTION: The extent of left atrial (LA) mechanical function recovery after creation of linear lesions using the loop catheter has not been determined. METHODS AND RESULTS: LA mechanical function was assessed before and after linear lesions using transthoracic two-dimensional and Doppler echocardiography in two groups: (1) normal, which consisted of eight healthy dogs in normal sinus rhythm (NSR); and (2) atrial fibrillation (AF), which consisted of nine dogs in spontaneous AF for 6 months following rapid pacing-induced AF. NSR was restored with linear lesions in all AF dogs. All animals were in NSR 5 months after linear lesions. In the normal dogs, the maximal velocity of the transmitral flow "A" wave was reduced by 42% during the first week postablation and by 24% at 5 months versus preablation. At 5 months, no differences in LA function were noted between the normal and the AF group for all measured Doppler parameters. At 5 months, the LA systolic area in AF dogs was reduced by 40% (preablation 12.9 +/- 2.9 cm2, postablation 7.6 +/- 1.2 cm2; P < 0.01) and in the normal dogs by 21% (preablation 10.0 +/- 0.9 cm2, postablation 7.8 +/- 1.2 cm2; P < 0.02), being the same in both groups within 3 months of recovery. CONCLUSION: The creation of linear lesions with the loop catheter does not result in LA expansion. In normal dogs, LA mechanical activity is reduced for 3 weeks postablation. The time course of LA mechanical function recovery is the same for the AF and the NSR dogs, and it is complete at 3 months postablation. At 5 months, LA systolic function parameters in both groups are reduced by 24% versus the preablation values of the normal dogs. Linear lesions result in a significant reduction in LA size.

Animals↗
PubMed2001

Effects of aging on left atrial reservoir, conduit, and booster pump function: a multi-institution acoustic quantification study.

OBJECTIVE: To assess the feasibility of measuring left atrial (LA) function with acoustic quantification (AQ) and then assess the effects of age and sex on LA reservoir, conduit, and booster pump function. PATIENTS AND SETTING: 165 subjects without cardiovascular disease, 3-79 years old, were enrolled by six tertiary hospital centres. INTERVENTIONS: Continuous LA AQ area data were acquired and signal averaged to form composite waveforms which were analysed off-line. MAIN OUTCOME MEASURES: Parameters of LA performance according to age and sex. RESULTS: Signal averaged LA waveforms were sufficiently stable and detailed to allow automated analysis in all cases. An age related increase in LA area was noted. LA reservoir function did not vary with age or sex. All parameters of LA passive and active emptying revealed a significant age dependency. Overall, the passive emptying phase accounted for 66% of total LA emptying ranging from 76% in the youngest to 44% in the oldest decade. LA contraction accounted for 34% of atrial emptying in all subjects combined with the older subjects being more dependent on atrial booster pump function. When adjusted for atrial size, there were no sex related differences in LA function. CONCLUSIONS: LA reservoir, conduit, and booster pump function can be assessed with automated analysis of signal averaged LA area waveforms. As LA performance varies with age, establishment of normal values should enhance the evaluation of pathologic states in which LA function is important.

Acoustics↗
PubMed2003

Decreased left atrial appendage flow velocity with atrial fibrillation caused by negative inotropic agents: report of two cases.

Although pharmacological agents are frequently used to control ventricular rate or restore sinus rhythm of patients with atrial fibrillation (AF), there are no reports of the relationship between those agents and left atrial appendage (LAA) function. Two cases of a decrease in LAA blood flow velocity caused by negative inotropic agents are presented as an indication that negative inotropic agents are a risk factor for systemic thromboembolism with AF.

Atenolol↗
PubMed1992

[Doppler echocardiographic assessment of left atrial and left ventricular function during right bundle branch block].

Electrocardiographic, echocardiographic and Doppler echocardiographic studies were performed in 44 patients with coronary heart disease and complete right bundle branch block. The patients were found to have an impaired phase pattern of left ventricular systole and diastole as more prolonged length of its isometric relaxation and contraction, lower economic feasibility and efficiency of its contraction, moderate dilation and hypertrophy. Hemodynamic abnormalities in the left heart in these patients are closely correlate with the changes in the phase pattern of right ventricular systole and they turn out to be so greater as the degree of its hypertrophy is. In complete right bundle branch block, left ventricular pump dysfunction leads to decreased cardiac output and cardiac index, increased total peripheral vascular resistance, thus predisposing to impaired greater circulation.

Adult↗
PubMed1992

[Clinical and functional correlations of left atrial excursion characteristics in patients with mitral valve diseases. Part II].

Left atrial myocardial excursions were intraoperatively recorded in patients with mitral valvular disease (33 patients with mitral stenosis and 17 with mitral regurgitations). Three types of atrial myocardial excursions were identified. There was a high correlation between the types of myocardial excursions and the incidence of heart failure. The patients with Types I and II myocardial excursions had no virtually heart failure, those with Type III showed the highest (70%) incidence of heart failure. It is concluded that intraoperative assessment of left atrial myocardial excursions is of great significance in patients with mitral valvular disease.

Adolescent↗
PubMed2005

Diastolic dysfunction and left atrial volume: a population-based study.

OBJECTIVES: We examined the association between diastolic function and left atrial volume indexed to body surface area (LAVi) in a population-based study. BACKGROUND: Atrial enlargement has been suggested as a marker of the severity and duration of diastolic dysfunction (DD). However, the association between DD and atrial enlargement and their individual prognostic implications in the population is poorly defined. METHODS: A cross-sectional sample of Olmsted County, Minnesota, residents > or =45 years of age (n=2,042) underwent comprehensive Doppler echocardiography and medical record review. RESULTS: The LAVi increased with worsening DD: 23 +/- 6 ml/m2 (normal), 25 +/- 8 ml/m2 (grade I DD), 31 +/- 8 ml/m2 (grade II DD), 48 +/- 12 ml/m2 (grades III to IV DD). In bivariate analyses, age, left ventricular mass index, and DD grade were positively associated, whereas female gender and ejection fraction (EF) were inversely associated with LAVi (p <0.001 for all). When controlling for age, gender, cardiovascular (CV) disease, EF, and left ventricular mass, grade II DD was associated with a 24%, and grade III to IV DD was associated with a 62% larger LA volume (p <0.0001 for both). The area under the receiver-operator characteristic curve for LAVi to detect grade I, grade II, or grade III to IV DD was 0.57, 0.81, and 0.98, respectively. Both DD and LAVi were predictive of all-cause mortality, but when controlling for DD, LAVi was not an independent predictor of mortality. CONCLUSIONS: These data suggest that DD contributes to LA remodeling. Indeed, DD is a stronger predictor of mortality; presumably it better reflects the impact of CV disease within the general population.

Aged↗
PubMed2001

Radiofrequency modified maze in patients with atrial fibrillation undergoing concomitant cardiac surgery.

OBJECTIVE: In the majority of patients with chronic atrial fibrillation the arrhythmia will persist after correction of the underlying structural abnormality. The maze procedure is an effective surgical method to eliminate atrial fibrillation and to restore atrial contractility. METHODS: In this study we used radiofrequency energy to create lines of conduction block in both atria during cardiac surgery as a modification of the maze III procedure. One hundred twenty-two patients with atrial fibrillation for at least 1 year and structural heart disease underwent open heart operation and a radiofrequency modified maze procedure. RESULTS: In 108 (89%) of 122 patients mitral valve surgery was performed, and in this group 86 patients (80%) underwent 121 concomitant procedures. Fourteen patients (11%) underwent cardiac surgery not involving the mitral valve. The additional crossclamp time required for the left atrial part of the radiofrequency modified maze procedure was 14 +/- 3 minutes. The in-hospital mortality rate was 4.1%. The overall 39-month survival was 90%, and freedom of atrial flutter or atrial fibrillation was 78.5% +/- 5.1%. Eighty-nine survivors with sinus, atrial rhythm, or atrioventricular sequential pacemaker had Doppler echocardiography, and right atrial transport function was documented in 83% and left atrial transport function in 77% of patients. CONCLUSION: We concluded that the radiofrequency modified maze procedure as an adjunctive procedure is safe, time-sparing, and effective in eliminating atrial fibrillation and restoring atrial transport function.

Aged↗
PubMed1996

Evaluation of left atrial appendage anatomy and function in recent-onset atrial fibrillation by transesophageal echocardiography.

Data regarding left atrial (LA) and LA appendage anatomy and function among patients with newly recognized atrial fibrillation (AF) who have not received long-term warfarin are currently unknown. To identify echocardiographic indexes which characterize those at increased risk for thrombus formation, we analyzed transesophageal echocardiographic studies in 100 consecutive patients with newly recognized AF (duration 2.6 +/- 0.3 week) who had not received long-term warfarin. Fourteen percent of patients had LA thrombi. LA thrombi were associated with larger LA appendages, more depressed LA appendage outflow velocities, and a higher prevalence of severe spontaneous LA contrast. Patients with spontaneous contrast had larger LA and LA appendage anatomy and lower LA appendage ejection velocity. Among patients presenting with their first episode of AF, greater LA appendage ejection and filling velocities and smaller LA and LA appendage sizes were seen among those with AF of <2 weeks duration compared with those with AF of >2 weeks. Thus, patients with recent onset AF and LA thrombi or spontaneous echo contrast have more dilated LA and LA appendage anatomy, and more depressed LA appendage systolic function. Data from patients with their first episode of AF suggests that AF is associated with rapid LA remodeling.

Adult↗
PubMed2002

Left atrial volume as a morphophysiologic expression of left ventricular diastolic dysfunction and relation to cardiovascular risk burden.

Left ventricular (LV) diastolic dysfunction is prevalent in the community. Current assessment of diastolic function can be complex, involving Doppler evaluation of an array of hemodynamic data. The relation between left atrial (LA) volume and diastolic function, and between LA volume and cardiovascular risk and disease burden are not well known. In the present prospective study of 140 adults, mean age 58 +/- 19 years, referred for a clinically-indicated echocardiogram and in sinus rhythm, with no history of atrial arrhythmias or valvular heart disease, we determined the LA volume, LV diastolic function status, cardiovascular risk score (based on age, gender, history of systemic hypertension, diabetes mellitus, hyperlipidemia, and smoking), and cardiovascular disease burden (based on confirmed vascular disease, congestive heart failure, and transient ischemic attack or stroke). LA volume was found to correlate positively with age, body surface area, cardiovascular risk score, LV end-diastolic and end-systolic dimensions, LV mass, diastolic function grade, tissue Doppler E/E', tricuspid regurgitation velocity, and negatively with LV ejection fraction (all p <0.006). In a multivariate clinical model, LA volume indexed to body surface area (indexed LA volume) was independently associated with cardiovascular risk score (p <0.001), congestive heart failure (p = 0.014), vascular disease (p = 0.012), transient ischemic attack or stroke (p = 0.021), and history of smoking (p = 0.008). In a clinical and echocardiographic model, indexed LA volume was strongly associated with diastolic function grade (p <0.001), independent of LV ejection fraction, age, gender, and cardiovascular risk score. In patients without a history of atrial arrhythmias or valvular heart disease, LA volume expressed the severity of diastolic dysfunction and provided an index of cardiovascular risk and disease burden.

Adolescent↗
PubMed2005

Left atrial volume, geometry, and function in systolic and diastolic heart failure of persons > or =65 years of age (the cardiovascular health study).

The left atrium enlarges in association with many factors, including aging, atrial fibrillation, hypertension, diastolic dysfunction, and heart failure (HF) with low ejection fraction. However, left atrial (LA) volume, geometry, and emptying have not been compared between diastolic and systolic HF, nor has the association of LA volume for new HF been determined in older subjects, many of whom have normal ejection fraction. We used echocardiography to measure the LA volume, geometry, and emptying in 851 community-dwelling subjects > or =65 years of age, including 180 with HF at baseline and 255 participants who subsequently developed HF. The LA volume, area, and linear dimensions were higher in the prevalent and incident HF groups than in controls and did not differ between those with systolic versus diastolic HF, independent of co-morbidities and Doppler measures of diastolic function. The fractional area change was associated with prevalent, but not incident, HF. In conclusion, in population-based older subjects, the LA size is increased and LA emptying decreased in patients with either systolic or diastolic HF. LA size is associated with the new development of HF. These findings highlight the important role of the left atrium in HF, with or without a decreased ejection fraction.

Aged↗
PubMed1999

Noninvasive assessment of left atrial maximum dP/dt by a combination of transmitral and pulmonary venous flow.

OBJECTIVES: The study assessed whether hemodynamic parameters of left atrial (LA) systolic function could be estimated noninvasively using Doppler echocardiography. BACKGROUND: Left atrial systolic function is an important aspect of cardiac function. Doppler echocardiography can measure changes in LA volume, but has not been shown to relate to hemodynamic parameters such as the maximal value of the first derivative of the pressure (LA dP/dt(max)). METHODS: Eighteen patients in sinus rhythm were studied immediately before and after open heart surgery using simultaneous LA pressure measurements and intraoperative transesophageal echocardiography. Left atrial pressure was measured with a micromanometer catheter, and LA dP/dt(max) during atrial contraction was obtained. Transmitral and pulmonary venous flow were recorded by pulsed Doppler echocardiography. Peak velocity, and mean acceleration and deceleration, and the time-velocity integral of each flow during atrial contraction was measured. The initial eight patients served as the study group to derive a multilinear regression equation to estimate LA dP/dt(max) from Doppler parameters, and the latter 10 patients served as the test group to validate the equation. A previously validated numeric model was used to confirm these results. RESULTS: In the study group, LA dP/dt(max) showed a linear relation with LA pressure before atrial contraction (r = 0.80, p < 0.005), confirming the presence of the Frank-Starling mechanism in the LA. Among transmitral flow parameters, mean acceleration showed the strongest correlation with LA dP/dt(max) (r = 0.78, p < 0.001). Among pulmonary venous flow parameters, no single parameter was sufficient to estimate LA dP/dt(max) with an r2 > 0.30. By stepwise and multiple linear regression analysis, LA dP/dt(max) was best described as follows: LA dP/dt(max) = 0.1 M-AC +/- 1.8 P-V - 4.1; r = 0.88, p < 0.0001, where M-AC is the mean acceleration of transmitral flow and P-V is the peak velocity of pulmonary venous flow during atrial contraction. This equation was tested in the latter 10 patients of the test group. Predicted and measured LA dP/dt(max) correlated well (r = 0.90, p < 0.0001). Numerical simulation verified that this relationship held across a wide range of atrial elastance, ventricular relaxation and systolic function, with LA dP/dt(max) predicted by the above equation with r = 0.94. CONCLUSIONS: A combination of transmitral and pulmonary venous flow parameters can provide a hemodynamic assessment of LA systolic function.

Adult↗