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.

SourceResearch connectionFrom yearThrough year

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

At least 1,369 records · Page 76Linked to original sources

PubMed2004

Activation of generalised inflammatory reaction following electrical cardioversion.

BACKGROUND: Restoration of sinus rhythm in patients with atrial fibrillation (AF) is associated with an increased risk of thrombo-embolic complications due to delayed return of the left atrial and left atrial appendage systolic function. Direct current cardioversion (DC), used for AF termination, may cause myocardial injury and subsequent activation of inflammatory response. A C-reactive protein (CRP) is a non-specific marker of inflammation. AIM: To examine the effects of external DC of AF or atrial flutter (AFlut) on inflammatory processes. METHODS: The study group consisted of 35 patients (20 females and 15 males, mean age 67.9+/-9.7 years, range 46-83 years) with paroxysmal or persistent AF/AFlut who underwent elective DC. CRP plasma concentration was measured before and 24 hours after DC. RESULTS: The mean total DC energy was 431.2 J. CRP plasma concentration increased significantly following DC - from 3.9+/-3.4 ng/ml before DC to 7.2+/-6.7 ng/ml after DC (p<0.0001). CRP level correlated with body mass index (r=0.34, p<0.05), however, this correlation became non-significant after inclusion of the presence of diabetes into the statistical model. There was also a positive correlation between CRP values before and after DC (r=0.72, p<0.0001). No correlation between CRP and gender, total power of DC nor the number of DC shocks was detected. CONCLUSIONS: External DC of AF/Aflut causes activation of inflammatory processes measured as a significant increase in the CRP plasma concentration.

Aged↗

PubMed1983

[Studies on systolic performance of the left atrium].

To analyze left atrial (LA) pump function, aortic root echocardiograms and LA pressure (P) by a Millar 's catheter tip manometer were recorded simultaneously in 26 patients (pts) in regular sinus rhythm [six normal subjects (C), three with angina pectoris (AP), eight with old myocardial infarction (MI), three with congestive cardiomyopathy (CCM), three with hypertension (HT), one with hypertrophic cardiomyopathy (HCM), one with mitral regurgitation and mild stenosis (MRs), and one with mitral regurgitation (MR)]. The pressure-dimension curve of the LA composed of two loops; an A-loop (pump function of the LA) and a V-loop. The following parameters were measured: Da = LA dimension at the beginning of the active atrial shortening, S-A-loop = the area of the A-loop, mean V = mean LA velocity of fractional fiber shortening, and peak T = maximum (LAP X LAD) during active atrial shortening phase. The S-A-loop was directly proportional to Da (r = 0.62, p less than 0.001) and the mean V was inversely correlated with the peak T (r = -0.76, p less than 0.001). This indicated that Starling's mechanism was operative and force-velocity relation exited in the LA. In HT, Da, the S-A-loop, the ratio of the S-A-loop to Da, and the ratio of mean V to peak T tended to be larger than those in other pts groups. Thus, the present results suggested that LA pump function was augmented in HT, probably due not only to Starling's effect but also to enhanced inotropic state of the LA.

Adult↗

PubMed1994

Echocardiographic evaluation of anuloplasty rings. Comparison of continuity equation and pressure half-time methods.

This study was undertaken to compare pressure half-time and continuity equation methods in the postoperative evaluation of anuloplasty rings. We performed 2-dimensional echocardiography and Doppler studies in 39 patients who had undergone valve repair for mitral regurgitation. In patients with a pressure half-time of 110 msec or more (9/39), there was no significant difference in calculated valve area between the 2 methods (p = 0.696). A significant difference was shown between the 2 methods (p < 0.001) in patients with a half-time less than 110 msec (30/39). When patients were classified according to the type of ring they had received, no significant difference was noted between the 2 groups with regard to peak and mean mitral gradients. In patients placed in subgroups according to half-times of less than 110 msec and half-times of 110 msec or more, no difference was noted between groups in terms of mean mitral gradient, presence of mitral regurgitation, left atrial size, left ventricular function, or heart rate. The continuity equation appears to provide much more homogeneous results in the calculation of valve area in patients who have undergone valvular repair for mitral valve regurgitation.

Adolescent↗

PubMed1993

[Acute electrophysiologic and echocardiographic changes induced by xamoterol in chronic chagasic patients with sinus node dysfunction].

PURPOSE: To evaluate xamoterol (Corwin)--a partial beta-adrenergic receptor agonist--in long-term chagasic patients with symptomatic sinus node dysfunction previously treated with permanent atrial pacemaker. METHODS: Ten patients with permanent AAI pacing were studied. Initially, in spontaneous rhythm (sinus rhythm due to inhibition of the pacemaker) and under atrial pacing with rate of 60, 80 and 100ppm with temporary external programming of the pulse generator were evaluated. Basic heart rate, maximal sinus node recovery time and the point at which Wenckebach AV block was achieved were recorded. After that, echocardiographic evaluation was performed to analyze the left ventricular performance with ejection fraction calculation and the percentage of the fractional shortening during spontaneous rhythm and under atrial pacing with rate of 60, 80 and 100ppm. This protocol was repeated after 5mg of intravenous xamoterol. RESULTS: Five men and 5 women (mean age of 46) were studied. Xamoterol increased the basic heart rate, the rate at which the Wenckebach AV block was achieved and shortened the maximal sinus node recovery time (statistically significant) suggesting a beta-adrenergic agonist action of the drug. Left ventricular performance showed significant improvement only when the values in sinus rhythm (during inhibition of the pulse generator) were compared. Under atrial pacing, left ventricular function was consistently improved in all patients but with no significance. CONCLUSION: Xamoterol showed to be a beta-adrenergic receptors agonist in long-term chagasic patients with sinus node dysfunction at rest, when the simpatic tone was low, with evident action on the electrophysiologic parameters.

Adult↗

PubMed1996

Doppler analysis of pulmonary venous flow profiles in orthotopic heart transplant recipients: a comparison with mitral flow profiles and atrial function.

Previous Doppler studies of transmitral flow profiles in heart transplant recipients suggested left ventricular (LV) diastolic dysfunction. The influence of left atrial filling and emptying on mitral Doppler profiles in heart transplant recipients has not been studied systematically. In the present study, pulmonary venous flow profiles, mitral flow profiles, left atrial area change and mitral annulus motion were analyzed in 20 orthotopic heart transplant recipient and 20 control subjects by transthoracic and transesophageal echocardiography and Doppler. Mitral flow profiles revealed a "restrictive" pattern with a high early-to-late diastolic flow velocity ratio in transplant patients (2.16 +/- 0.52 vs. 1.30 +/- 0.25, p < 0.0001), which was mainly due to a reduced late diastolic maximum mitral flow velocity (32.6 +/- 8.3 vs. 51.6 +/- 12.4 cm/s, p < 0.0001). Left atrial area change (35.9 +/- 13.9 vs. 58.1 +/- 17.0%, p < 0.0006) and mitral annulus motion (9.2 +/- 3.3 vs. 12.2 +/- 2.0%, p < 0.05) were reduced in transplant recipients, compared to controls. Pulmonary venous flow parameters in transplant recipients were markedly altered during systole, when pulmonary venous flow parameters are influenced primarily by atrial function rather than by diastolic LV properties: peak systolic flow velocity (45.5 +/- 8.2 vs. 62.3 +/- 14.0 cm/s, p < 0.001), maximum flow velocity ratio (0.87 +/- 0.19 vs. 1.45 +/- 0.33), time velocity integral of pulmonary venous flow during systole (9.3 +/- 2.3 vs. 17.1 +/- 4.0 cm, p < 0.001) and the systolic fraction of the time velocity integral (52.6 +/- 10.8 vs. 68.5 +/- 6.8%, p < 0.001) were lower in heart transplant recipients than in controls. These findings are compatible with atrial dysfunction and reduced mitral annulus motion. The results of this study indicate that LV diastolic dysfunction is not the only possible cause of altered transmitral Doppler profiles in heart transplant recipients. Atrial abnormalities represent a major contributing factor to altered mitral and pulmonary venous flow patterns. Analysis of transmitral Doppler profiles alone are therefore not adequate for analysis of diastolic LV function in heart transplant recipients.

Adult↗

PubMed1981

Follow-up study in congestive (dilated) cardiomyopathy.

A follow-up study was carried out in 98 patients with congestive cardiomyopathy using clinical data and M-mode echocardiography. 59 patients survived (mean follow-up period 18 months), 39 patients died (mean survival period 12.6 months). Median survival time was 3 years. Prognosis was unfavorably affected by ECG signs (left bundle branch block, atrial fibrillation, ventricular premature beats), functional class 4, and left ventricular dysfunction presented by mitral E-point separation over 25 mm, left atrial dimension of 50 mm or more and posterior wall systolic thickening less than 50%. Age, excessive alcohol intake, left ventricular enddiastolic dimension or wall thickness did not affect prognosis. M-mode restudies preformed in 59 patients included a variable course within 2 years after first presentation but a progressive impairment of left ventricular function in mor than 2 years of follow-up.

Adolescent↗

PubMed1995

Increased markers of thrombogenesis in chronic atrial fibrillation: effects of warfarin treatment.

OBJECTIVE: To determine whether chronic atrial fibrillation is associated with abnormalities in plasma fibrinogen, von Willebrand factor (vWF) (a marker of endothelial disturbance), or fibrin D- dimer (a measure of fibrin turnover); and if so, whether such levels are related to haemodynamic disturbance (enlarged left atrium, poor left ventricular function) or existing treatment with warfarin or aspirin. To investigate the effects of introducing warfarin in patients with atrial fibrillation on fibrinogen and D- dimer levels. DESIGN: Cross sectional population sample controlled study and longitudinal study of patients undergoing anticoagulation. SETTING: District general hospital. SUBJECTS: 87 patients (44 men and 43 women of mean (SEM) age 63.0 (1.0)) with chronic atrial fibrillation. At the time of the study, 37 were taking no antithrombotic medication (group 1), 31 were taking warfarin (including two on warfarin and aspirin) (group 2) and 19 were taking aspirin alone (group 3). They were compared with 158 population controls from a random population sample (the second Glasgow monitoring trends and determinants in cardiovascular disease study). As part of clinical treatment warfarin was introduced in 20 patients with chronic atrial fibrillation (14 men and six women of mean (SEM) (range) age 63.9 (2.35 (32-74) years). RESULTS: Plasma fibrinogen remained significantly increased in patients of group 1 (no antithrombotic medication) compared with that of the population controls (median difference 1.23 g/l; 95% confidence interval (CI) 0.88 to 1.62, P < 0.0001). There was also a significant increase in plasma D-dimer levels (median difference 77 ng/ml; 95% CI 38 to 122, P < 0.01) and vWF (median difference 63 IU/dl; 95% CI 38 to 89, P < 0.0001). There was no significant difference in plasma fibrinogen (median difference 0.14 g/l; 95% CI -0.44 to 0.77, P = 0.65) or vWF (median difference 3.5 IU/dl; 95% CI - 41 to 41, P = not significant in patients of group 2 (warfarin treatment) compared with that of patients in group 1. Levels of D-dimer were significantly lower in group 2 (median difference 90 ng/ml, 95% CI 39 to 150, P < 0.0001) than in group 1. There were no significant differences in plasma fibrinogen (median difference 0.08 g/l; 95% CI - 0.52 to 0.77, P = 0.73), D-dimer (median difference - 34 ng/ml; 95% CI - 114 to 21.0, P = 0.25), or vWF (median difference 2%; 95% CI - 35 to 41, P = not significant) levels between patients of groups 1 and 3. There were no significant correlations between the coagulation indices and left atrial volume or ventricular function. There was a significant positive correlation between plasma fibrin D-dimer and vWF levels in patients of groups 1 and 3 (r = 0.52, P < 0.001). There was a significant reduction in median plasma fibrin D-dimer levels at 2 months after the introduction of warfarin (181 ng/ml v 80 ng/ml, P < 0.001), but no effect on plasma fibrinogen. CONCLUSIONS: Increased median plasma fibrinogen and vWF levels were found in patients with chronic atrial fibrillation. Plasma D-dimer levels were also increased in patients with chronic atrial fibrillation not receiving warfarin, suggesting increased intravascular thrombogenesis in such patients. Introduction of warfarin normalised circulating fibrin D- dimer levels, suggesting that warfarin treatment was effective in preventing excessive fibrin turnover, consistent with the antithrombotic effects of warfarin. These results suggest three possible thrombotic markers to assess patients with atrial fibrillation who are at high risk of thrombogenesis; D-dimer also merits assessment as a measure of reduction in thrombotic risk in patients receiving warfarin.

Adult↗

PubMed2026

Cardiac remodelling and dysfunction in cancer patients receiving cardiotoxic therapies: proteomic and metabolomic profiling.

BACKGROUND AND AIMS: The objective of this study was to define the relationships between the circulating proteome and metabolome with cardiac structure and function in patients with breast cancer receiving cardiotoxic therapies. METHODS: Proteomics and metabolomics profiling was performed in a longitudinal, prospective cohort study of breast cancer patients receiving anthracyclines and/or trastuzumab, using the Olink Explore 3072 platform and rapid liquid chromatography-mass spectrometry, respectively. Multivariable linear mixed-effect models evaluated the contemporaneous (same visit) and lagged (subsequent visit) associations between repeated measures of individual proteins or metabolites with quantitative echocardiographic measures of cardiac structure [left ventricular (LV) mass and left atrial volume index] and function [LV ejection fraction (LVEF), longitudinal and circumferential strain, E/e', and ventricular-arterial coupling]. Cox regression and pathway enrichment analyses were conducted for biomarkers demonstrating significant associations with cardiac function. RESULTS: Across 547 breast cancer participants (median age 50 years), 203 unique proteins and 16 unique metabolites were significantly associated with measures of cardiac structure and function in contemporaneous and lagged analyses. Notably, cathepsin C was associated with LVEF [false discovery rate (FDR), P = .017], longitudinal strain (FDR, P = .046), left atrial volume index (FDR, P = .035), and incident cardiac dysfunction, defined by an LVEF decline ≥10% to <50% (hazard ratio .61, 95% confidence interval .41, .90). The 147 proteins associated with cardiac function were enriched in biological processes reflective of protein deubiquitination, protein modification by small protein removal, macromolecule catabolic processes, and global metabolic pathways. Individual metabolites significantly associated with cardiac function (LVEF, longitudinal strain) included n-acetylglutamine, aspartic acid, acetylasparagine, alanyl-alanine, and prolyl-glycine (FDR, P-value < .001), and belonged to amino acids and derivatives and peptides. CONCLUSIONS: These findings provide translational insights into cancer therapy-related cardiac dysfunction and remodelling and identify potential new biomarkers of cardiotoxicity. There is an important need for validation of these findings and a deeper understanding of the biology of these biomarkers.

Humans↗

PubMed2004

Catheter ablation for atrial fibrillation in congestive heart failure.

BACKGROUND: Congestive heart failure and atrial fibrillation often coexist, and each adversely affects the other with respect to management and prognosis. We prospectively evaluated the effect of catheter ablation for atrial fibrillation on left ventricular function in patients with heart failure. METHODS: We studied 58 consecutive patients with congestive heart failure and a left ventricular ejection fraction of less than 45 percent who were undergoing catheter ablation for atrial fibrillation. We selected as controls 58 patients without congestive heart failure who were undergoing ablation for atrial fibrillation, matched according to age, sex, and classification of atrial fibrillation. We evaluated the patients' left ventricular function and dimensions, symptom score, exercise capacity, and quality of life at baseline and at months 1, 3, 6, and 12. RESULTS: After a mean (+/-SD) of 12+/-7 months, 78 percent of the patients with congestive heart failure and 84 percent of the controls remained in sinus rhythm (P=0.34) (69 percent and 71 percent, respectively, were in sinus rhythm without the administration of antiarrhythmic drugs). The patients with congestive heart failure had significant improvement in left ventricular function (increases in the ejection fraction and fractional shortening of 21+/-13 percent and 11+/-7 percent, respectively; P<0.001 for both comparisons), left ventricular dimensions (decreases in the diastolic and systolic diameters of 6+/-6 mm and 8+/-7 mm, respectively; P=0.03 and P<0.001, respectively), exercise capacity, symptoms, and quality of life. The ejection fraction improved significantly not only in patients without concurrent structural heart disease (24+/-10 percent, P<0.001) and those with inadequate rate control before ablation (23+/-10 percent, P<0.001), but also in those with coexisting heart disease (16+/-14 percent, P<0.001) and adequate rate control before ablation (17+/-15 percent, P<0.001). CONCLUSIONS: Restoration and maintenance of sinus rhythm by catheter ablation without the use of drugs in patients with congestive heart failure and atrial fibrillation significantly improve cardiac function, symptoms, exercise capacity, and quality of life.

Aged↗

PubMed1989

Plasma concentrations of atrial natriuretic factor during positive end-expiratory pressure ventilation in dogs with normal or impaired left ventricular function.

The influence of positive end-expiratory pressure (PEEP) ventilation on plasma concentrations of atrial natriuretic factor (ANF) was studied in dogs anesthetized with sodium pentobarbital during normal cardiac function and during acutely impaired left ventricular function. Left ventricular impairment was induced by injecting repeated doses of polystyrene microspheres with a diameter of 50 microns into the main left coronary artery, causing a severe depression of left ventricular performance. This was accompanied by doubling of ANF concentrations measured in blood sampled from aorta. Application of PEEP (10 cmH2O (0.98 kPa] reduced plasma ANF in dogs both with normal and impaired left ventricular function. The decrease was significantly greater during left ventricular impairment compared to control, 31 and 19%, respectively. A positive correlation was observed between plasma ANF and transmural left ventricular end-diastolic pressure when all data were pooled, but not between ANF and transmural right atrial pressure. This implies that transmural left ventricular end-diastolic and hence transmural left atrial pressure probably is the principal determinant of acute ANF release in this model. Reduced plasma ANF in response to PEEP even during acute left ventricular impairment when ANF release was augmented, was probably due to diminished atrial distension during PEEP ventilation.

Animals↗

PubMed2001

Reversible impairment of left and right ventricular systolic and diastolic function during short-lasting atrial fibrillation in patients with an implantable atrial defibrillator: a tissue Doppler imaging study.

AF with a fast ventricular response may cause ventricular mechanical impairment, though whether short-lasting AF with satisfactory rate control may affect ventricular function is unknown. This study investigated if prompt cardioversion by an implantable atrial defibrillator (IAD) may prevent left (LV) and right ventricular (RV) systolic and diastolic dysfunction. Ten patients (mean age 61 +/- 9 years, 8 men) with paroxysmal AF without structural heart disease who received an IAD were studied by echocardiography and tissue Doppler imaging (TDI) for both ventricles. Measurements were made during baseline sinus rhythm and at 1-minute, 20-minute, 4-hour, and 1-week postcardioversion of an episode of spontaneous AF. The occurrence of AF and the ventricular rate were monitored at 2-hour intervals by the device. There were 50 episodes of AF with a mean duration of 8.8 +/- 8.9 days (2 hours to 37 days). There was no difference in M-mode measured LV fractional shortening and ejection fraction between baseline sinus rhythm and after cardioversion. However, the TDI derived myocardial systolic velocity (TDI-S) was significantly lower at 1-minute postcardioversion and was normalized at 1 week in both LVs (baseline: 5.7 +/- 1.8, 1 minute: 4.2 +/- 1.0, 20 minutes: 4.3 +/- 0.9, 4 hours: 4.8 +/- 1.0, 1 week: 5.5 +/- 1.8 cm/s; P < 0.005 when comparing 1 minute and 20 minutes to baseline; P < 0.05 when comparing 4 hour to baseline) and RV (baseline: 10.4 +/- 2.1, 1 minute: 7.8 +/- 1.4, 20 minutes: 8.1 +/- 1.2, 4 hours: 9.2 +/- 1.5, 1 week: 10.0 +/- 2.0 cm/s; P < 0.005 when comparing 1 minute, 20 minutes, and 4 hours to baseline). For diastolic function, transmitral Doppler study showed a decrease in early filling velocity at 1 minute (P < 0.05) and 20 minutes (P < 0.005), which was normalized at 4 hours. There was no change in transtricuspid Doppler flow. However, TDI derived myocardial early filling velocity was decreased in the LV (baseline: 6.0 +/- 2.8, 1 minute: 5.4 +/- 2.3, 20 minutes: 5.4 +/- 2.1, 4 hours: 6.1 +/- 2.2, 1 week: 5.8 +/- 1.7 cm/s; P < 0.05 when comparing 1 minute and 20 minutes to baseline) and RV (baseline: 8.9 +/- 3.5, 1 minute: 7.9 +/- 3.3, 20 minutes: 8.1 +/- 3.3, 4 hours: 8.5 +/- 2.9, 1 week: 8.4 +/- 3.5 cm/s; P < 0.05 when comparing 1 minute to baseline). AF of a longer duration (> 48 hours) resulted in a more depressed TDI-S in LV (> 48 hours: 4.2 +/- 1.0, < or = 48 hours: 5.3 +/- 1.3 cm/s; P < 0.01). Shocks in sinus rhythm did not affect any of the above echocardiographic parameters. Therefore, despite adequate rate control, short-lasting AF impairs systolic and diastolic function in both ventricles, which improves gradually after cardioversion. Early restoration of sinus rhythm by an IAD minimizes ventricular dysfunction. TDI is a sensitive tool to assess early systolic and diastolic dysfunction.

Atrial Fibrillation↗

PubMed1988

Postoperative hypertension: a comparison of diltiazem, nifedipine, and nitroprusside.

In previous studies, the treatment of postoperative hypertension with sodium nitroprusside induced ischemic metabolism without a decrease in coronary sinus blood flow. In contrast, the calcium antagonists diltiazem and nifedipine reduce blood pressure and may improve myocardial metabolism. A prospective randomized trial was performed in 62 patients, in whom hypertension developed (mean arterial pressure greater than 95 mm Hg) after coronary bypass procedures, to compare diltiazem (n = 22), nifedipine (n = 20), and nitroprusside (n = 20). All three agents reduced blood pressure equally (p less than 0.0001, by analysis of variance). Heart rate decreased with diltiazem (p = 0.006) but increased with nifedipine and nitroprusside (p less than 0.05). Left ventricular diastolic function (the relation between left atrial pressure and left ventricular end-diastolic volume) was not changed with the three drugs. Systolic function (the relation between systolic blood pressure and left ventricular end-systolic volume) was depressed with diltiazem (p = 0.05 by analysis of covariance) and nifedipine (p = 0.05) but not with nitroprusside. Myocardial performance (the relation between left ventricular stroke work index and end-diastolic volume) was depressed most by diltiazem (p = 0.001 by analysis of covariance), and to a lesser extent with nifedipine (p = 0.03), but not with nitroprusside. Myocardial lactate flux in response to the stress of atrial pacing decreased with nitroprusside but not with diltiazem or nifedipine (p = 0.03 by analysis of variance). Diltiazem and nifedipine are effective agents for treating postoperative hypertension after coronary artery bypass operations.

Clinical Trials as Topic↗

PubMed2003

[Physiopathology and etiology of mitral insufficiency].

Mitral regurgitation has a complex pathophysiology. It should be assessed from the study of factors influencing regurgitant volume and the evaluation of hemodynamics effects downstream (impact on left ventricular function) and upstream (level of left atrial compliance and pulmonary pressure). The regurgitant volume is larger when the regurgitation time is longer, the regurgitant orifice is bigger and the magnitude of the left ventrico-atrial systolic gradient higher. The study of left ventricular function is difficult, especially in chronic mitral regurgitation where the apparently normal left ventricular systolic function can hide a significant worsening in myocardiacs fibres contractile abilities. With the increase in life expectancy and with the decrease in the incidence of rheumatic fever, aetiologies of mitral regurgitation have changed in the past 30 years. They are now dominated by dystrophic mitral regurgitation and infective endocarditis while rheumatic fever becomes less frequent.

Endocarditis, Bacterial↗

PubMed2005

Tissue Doppler echocardiographic evidence of atrial mechanical dysfunction in coronary artery disease.

BACKGROUND: Atrial function is an integral part of cardiac function which is often neglected. The presence of coronary artery disease (CAD) may impair atrial function. This study investigated if atrial mechanical dysfunction was present in patients with CAD by tissue Doppler echocardiography (TDI). METHODS: Echocardiography with TDI was performed in 118 patients with CAD, and compared with 100 normal controls with comparable age and heart rate. Regional atrial function was assessed at the left (LA) and right (RA) atrial free wall and inter-atrial septum (IAS). The peak regional atrial contraction velocity of (V(A)) and the timing of mechanical events were compared. RESULTS: The V(A) in the LA (5.0+/-2.6 Vs 7.7+/-2.6 cm/s), IAS (4.8+/-1.7 Vs 5.7+/-1.5 cm/s) and RA (6.8+/-3.1 Vs 9.2+/-2.9 cm/s) were significantly decreased in patients with CAD when compared with controls (all p<0.001). Patients with impaired systolic function (ejection fraction 50% (both p<0.001); and were lower in those with restrictive filling pattern (RFP) than non-RFP of diastolic dysfunction (both p<0.05). The V(A) in all the subgroups was lower than controls. In contrast, transmitral atrial velocity was unable to reveal any abnormality except in the subgroup with a RFP. The LA dimension, area and volume were increased in the disease groups, but were largely unchanged in the RA despite abnormal V(A). The physiological inter-atrial delay for the onset and peak atrial contraction between the RA and LA were unaffected by CAD. CONCLUSIONS: The atrial contractile function in both atria was impaired in the presence of CAD, especially in the LA. This was detected even in patients with preserved systolic function or mild diastolic dysfunction such as non-RFP. Direct assessment of atrial velocity by TDI may better reflect atrial mechanical function than transmitral atrial velocity.

Atrial Function, Right↗

PubMed1986

Safety of prolonged aortic clamping with blood cardioplegia. III. Aspartate enrichment of glutamate-blood cardioplegia in energy-depleted hearts after ischemic and reperfusion injury.

This study tests the hypothesis that aspartate enrichment of glutamate-blood cardioplegia improves metabolic and functional recovery after ischemic and reperfusion damage. Ischemic and reperfusion damage were produced in 15 dogs by 45 minutes of aortic clamping at 37 degrees C and 5 minutes of blood reperfusion, before 2 more hours of aortic clamping (simulated operation). Six received multidose blood cardioplegia at 4 degrees C. In nine others, the cardioplegic solution was infused at 37 degrees C for the first 5 minutes, followed by multidose infusions at 4 degrees C. Four received 26 mmol glutamate-enriched cardioplegic solution. In five, the glutamate (13 mmol) cardioplegic solution was enriched with aspartate (13 mmol). Oxygen uptake and ventricular function (stroke work index, left atrial pressure) were measured. These data suggest aspartate enrichment produced the highest oxygen uptake (32 +/- 4 versus 17 +/- 2 ml/100 gm for glutamate and 7 +/- 1 ml/100 gm for 4 degrees C blood cardioplegia). Complete functional recovery occurred in aspartate/glutamate-treated hearts (stroke work index 90% +/- 4%, left atrial pressure 12 +/- 2 mm Hg), whereas recovery was incomplete with both glutamate alone (stroke work index 66% +/- 14%, left atrial pressure 20 +/- 3 mm Hg) and 4 degrees C blood cardioplegia at low cardiac outputs. Eight of 10 hearts not receiving aspartate failed at high cardiac outputs. Aspartate enrichment of glutamate-blood cardioplegia improves recovery after severe ischemic/reperfusion damage by improving oxidative metabolism during cardioplegic infusion and during postischemic work.

Animals↗

PubMed1987

Monitoring effects of alpha-human atrial natriuretic polypeptide (alpha-hANP) on left ventricular function in patients with essential hypertension with a cardiac probe.

The effects of alpha-hANP on left ventricular function were studied with a cardiac probe in ten patients with essential hypertension. Our data showed that intravenous administration of alpha-hANP significantly elevated left ventricular function. At 5 min, the elevation of EF, RCO, ER, RSV, PFR were 13.23% (P less than 0.02), 12.7 (P less than 0.02), 0.618 (P less than 0.02), 0.133 (P less than 0.05), 0.283 (P less than 0.01), respectively. At 10 min, the increase of EF, ER, were 11.07% (P less than 0.02) and 0.233 (P less than 0.01), respectively. Atriopeptin significantly reduced systolic and diastolic blood pressure from 2 min to 20 min (P less than 0.001-0.05).

Adult↗

PubMed1985

Noninvasive assessment of pacemaker hemodynamics by Doppler echocardiography: importance of left atrial size.

The relative decrease in cardiac output with ventricular pacing versus "physiologic" modes was measured noninvasively using Doppler echocardiography in 26 patients. Standard echocardiographic measurements of left ventricular size (diastolic diameter), left ventricular function (shortening fraction) and left atrial size were examined to determine which of these variables might best identify patients more likely to benefit from maintenance of atrioventricular (AV) synchrony. Decreases in relative cardiac output, expressed as reduction in the Doppler-derived flow velocity integral, with loss of AV synchrony ranged from 0 to 43% (mean decrease 21%). There was no correlation between left ventricular size or function and effect of pacing mode on relative cardiac output. There was, however, correlation between left atrial size and sensitivity to pacing mode. Patients with normal left atrial size were significantly more sensitive to loss of AV synchrony. In this subgroup, the decrease in flow velocity integral with ventricular pacing was 32 +/- 11% compared with only 11 +/- 13% in patients with left atrial enlargement. Thus, Doppler echocardiography is useful in assessing optimal pacing mode in the individual patient. Echocardiographically measured left atrial size may identify patients in whom physiologic pacing may be major benefit.

Adult↗

PubMed1990

[Successful surgical treatment of automatic atrial tachycardia].

A 3-year-old boy had chronic repetitive atrial tachycardia. The tachycardia could not be induced neither terminated with rapid atrial pacing nor atrial extrastimuli. Overdrive suppression and warm-up phenomenon were demonstrated. These electrophysiological features suggested atrial ectopic automaticity. Endocardial and epicardial mapping determined the origin of tachycardia at the left atrial appendage. The LA appendage was excised and the tachycardia was completely terminated. The patient is asymptomatic without medication and echocardiographic indices of left ventricular function returned to normal over 1 year follow-up period.

Child, Preschool↗