Echocardiographic Left Atrial Size Research Articles

Determination of radiographic vertebral heart score and vertebral left atrial size cutoffs based on echocardiographic left atrial size in dogs with myxomatous mitral valve disease.

Progression of myxomatous mitral valve disease (MMVD) in dogs is a common cause of left atrial enlargement. Recently, a classification of left atrial (LA) size based on echocardiographic measurement has been proposed. This study aims to determine the radiographic LA size by reporting the cutoff values of VHS and VLAS for different groups of echocardiographic-measured LA size in dogs with MMVD. This retrospective analytical cross-sectional study included dogs diagnosed with MMVD grouped based on the echocardiographic LA size into normal (LA/Ao<1.6), mild (1.6-1.89), moderate (1.9-2.2), and severe enlargement (>2.2) and were compared with ACVIM classification. VHS and VLAS were measured on the right lateral radiograph for each dog and cutoff values were calculated. One hundred and three dogs with MMVD were included in the study. A very strong positive correlation was observed between LA/Ao ratio and VHS (rs , 0.823, P<.01) or VLAS (rs , 0.834, P<.01). For VHS, a cutoff of 10.7 v, 11 v, and 11.5 v were established for echocardiographic LA thresholds of 1.6, 1.9, and 2.2 with a sensitivity of 79%, 92%, and 90% and a specificity of 97%, 90.7%, and 78.1%, respectively. For VLAS, a cutoff of 2.5 v, 2.7 v, and 2.9 v were established for echocardiographic LA cutoffs of 1.6, 1.9, and 2.2 with a sensitivity of 73%, 80%, and 83.3% and a specificity of 94%, 92%, and 86.3%, respectively. The results of this study may facilitate clinical decisions based on radiographic examination in dogs with myxomatous mitral valve disease.

Correlation Between CHA2DS2-VASc Score and Left Atrial Size in Patients With Atrial Fibrillation: A More Than 15-Year Prospective Follow-Up Study.

Background: Left atrial (LA) size represents atrial fibrillation (AF) burden and has been shown to be a predictor for AF stroke. The CHA2DS2-VASc score is also a well-established predictor of AF stroke. It is unknown to cardiologists whether these two risk scores are correlated, whether both are independent prognostic predictors and complimentary to each other, or whether one of them is a major determinant of stroke risk for AF patients.Method: A total of 708 patients from the National Taiwan University Atrial Fibrillation Registry were longitudinally followed up for more than 15 years. Left atrial size was measured by M mode of echocardiography. Adverse thromboembolic endpoints during follow-up were defined as ischemic stroke or transient ischemic attack.Results: The mean age was 72.1 ± 12.9 years, with 53% men. Both LA size and CHA2DS2-VASc score were associated with the risk of stroke in univariate analyses. There was a weak but significant positive correlation between LA size and CHA2DS2-VASc score (r = 0.17, P < 0.0001). Patients with higher CHA2DS2-VASc scores had a higher mean LA size (P < 0.01 for trend). When combining LA size and CHA2DS2-VASc score in the multivariable Cox model, only CHA2DS2-VASc score remained statistically significant [HR 1.39 (1.20–1.63); P < 0.001].Conclusion: LA size is not an independent predictor of AF stroke, and calculation of CHA2DS2-VASc score may be an alternative to measurement of echocardiographic LA size when evaluating the risk of stroke for AF patients.

Predictive value of echocardiographic left atrial size for incident stoke and stroke cause mortality: a population-based study

ObjectivesTo investigate the associations between echocardiographic left atrial (LA) size and incident stoke and stroke cause mortality among a rural population in China.DesignA prospective study.Setting and participantsBased on the Northeast...

Evaluation of radiographic predictors of left heart enlargement in dogs with known or suspected cardiovascular disease

Radiographic assessment of heart size is important for clinical management of dogs with cardiovascular disease (CVDz). We sought to compare the ability of vertebral heart size (VHS), vertebral left atrial size (VLAS), and radiologists' assessment of left atrial size (RadLAE) to predict echocardiographic left atrial size (EchoLAE), an important marker of left heart disease severity. We also compared the ability of VHS and VLAS to predict echocardiographic criteria for ACVIM stage B2 (EchoB2) in dogs with myxomatous mitral valve disease (MMVD). This prospective observational study enrolled 183 dogs with known or suspected CVDz that had an echocardiographic examination and thoracic radiographs obtained within 24 h. Compared to increased VHS, VLAS>2.3 was a more accurate predictor of EchoLAE (P=.002). VLAS>2.3 and RadLAE (both P<.0001) were independently associated with EchoLAE but VHS was not (P=.45). Optimal cutoffs for VLAS and VHS to predict EchoLAE were>2.3 vertebrae (sensitivity [Sn]=90.3%, specificity [Sp]=73.6%) and>11.1 vertebrae (Sn=75.8%, Sp=76.0%), respectively. Diagnostic accuracy of VLAS (AUC 0.84, 95% CI 0.73-0.92) and VHS (AUC 0.78, 95% CI 0.66-0.88) to predict EchoB2 in dogs with subclinical MMVD (n=64) were not significantly different (P=.17). Results demonstrate that VLAS and RadLAE were superior indicators of EchoLAE compared to VHS in dogs with known or suspected CVDz. Both VLAS and VHS are useful predictors of EchoB2 in dogs with subclinical MMVD. When echocardiography is unavailable, VLAS represents a useful radiographic measurement to aid clinical management of dogs with known or suspected CVDz.

Cross-Sectional Associations between Homoarginine, Intermediate Phenotypes, and Atrial Fibrillation in the Community-The Gutenberg Health Study.

Homoarginine has come into the focus of interest as a biomarker for cardiovascular disease. Atrial fibrillation (AF) causes a substantial increase in morbidity and mortality. Whether circulating homoarginine is associated with occurrence or persistence of AF and may serve as a new predictive biomarker remains unknown. We measured plasma levels of homoarginine in the population-based Gutenberg health study (3761 patients included, of them 51.7% males), mean age 55.6 ± 10.9 years-old. Associations between homoarginine and intermediate electrocardiographic and echocardiographic phenotypes and manifest AF were examined. Patients with AF (124 patients, of them 73.4% males) had a mean age 64.8 ± 8.6 years-old compared to a mean age of 55.3 ± 10.9 in the population without AF (p-value < 0.001) and showed a less beneficial risk factor profile. The median homoarginine levels in individuals with and without AF were 1.9 μmol/L (interquartile range (IQR) 1.5–2.5) and 2.0 μmol/L (IQR 1.5–2.5), respectively, p = 0.56. In multivariable-adjusted regression analyses homoarginine was not statistically significantly related to electrocardiographic variables. Among echocardiographic variables beta per standard deviation increase was −0.12 (95% confidence interval (CI) −0.23–(−0.02); p = 0.024) for left atrial area and −0.01 (95% CI −0.02–(−0.003); p = 0.013) for E/A ratio. The odds ratio between homoarginine and AF was 0.91 (95% CI 0.70–1.16; p = 0.45). In our large, population-based cross-sectional study, we did not find statistically significant correlations between lower homoarginine levels and occurrence or persistence of AF or most standard electrocardiographic phenotypes, but some moderate inverse associations with echocardiographic left atrial size and E/A. Homoarginine may not represent a strong biomarker to identify individuals at increased risk for AF. Further investigations will be needed to elucidate the role of homoarginine and cardiac function.

Interreader agreement of radiographic left atrial enlargement in dogs and comparison to echocardiographic left atrial assessment

IntroductionAssessing left atrial (LA) size is an integral part of the cardiac evaluation in dogs. Left atrial size is routinely evaluated by thoracic radiographs or echocardiography. ObjectivesThe objectives of the study were to assess agreement of subjective radiographic left atrial enlargement (LAE) between readers, to compare subjective radiographic LAE with echocardiography, and to assess the accuracy and reliability of commonly used Roentgen signs for LAE. AnimalsOne hundred one dogs with thoracic radiographs and echocardiography performed on the same day at a veterinary teaching hospital were retrospectively reviewed. MethodsThoracic radiographs were reviewed by two cardiologists, two radiologists, and two small animal rotating interns. Radiographs were evaluated for the subjective presence and severity of LAE and for seven Roentgen signs. Echocardiographic LA size was evaluated objectively by the left atrial-to-aortic root ratio and LA volume indexed to body weight. Interreader agreement of radiographic LAE evaluation and agreement between radiographic LAE assessment and echocardiographic LAE were assessed by linearly weighted kappa and intraclass correlation coefficient. ResultsInterreader agreement for the presence and degree of radiographic LAE ranged from moderate to substantial. The agreement between subjective radiographic LAE and echocardiographic LAE was moderate. Single Roentgen signs had poor to fair correlation with echocardiographic LAE. ConclusionsThe present study found that interreader agreement for radiographic classification of LAE was substantial among specialists and moderate for all readers. Subjective, global assessment of radiographic LAE is better than using any single Roentgen sign.

Alcohol Consumption, Left Atrial Diameter, and Atrial Fibrillation.

BackgroundAlcohol consumption has been associated with atrial fibrillation (AF) in several epidemiologic studies, but the underlying mechanisms remain unknown. We sought to test the hypothesis that an atrial myopathy, manifested by echocardiographic left atrial enlargement, explains the association between chronic alcohol use and AF.Methods and ResultsWe evaluated the relationship between cumulative alcohol consumption and risk of incident AF in 5220 Offspring and Original Framingham Heart Study participants (mean age 56.3 years, 54% women) with echocardiographic left atrial size measurements. The incidence of AF was 8.4 per 1000 person‐years, with 1088 incident AF cases occurring over a median 6.0 years (25th–75th percentiles 4.0–8.7 years) of follow‐up. After multivariable adjustment for potential confounders, every additional 10 g of alcohol per day (just under 1 drink per day) was associated with a 0.16 mm (95% CI, 0.10–0.21 mm) larger left atrial dimension. Also in multivariable adjusted analysis, every 10 g per day of alcohol consumed was associated with a 5% higher risk of developing new‐onset AF (hazard ratio, 1.05; 95% CI, 1.01–1.09). An estimated 24% (95% CI, 8–75) of the association between alcohol and AF risk was explained by left atrial enlargement.ConclusionsOur study of a large, community‐based sample identified alcohol consumption as a predictor of left atrial enlargement and subsequent incident AF. Left atrial enlargement may be an intermediate phenotype along the causal pathway linking long‐term alcohol consumption to AF.

A valentine-shaped cardiac silhouette in feline thoracic radiographs is primarily due to left atrial enlargement.

Conflicting information has been published regarding the cause of a valentine-shaped cardiac silhouette in dorsoventral or ventrodorsal thoracic radiographs in cats. The purpose of this retrospective, cross-sectional study was to test the hypothesis that the valentine shape is primarily due to left atrial enlargement. Images for cats with a radiographic valentine-shaped cardiac silhouette and full echocardiography examination were retrieved and independently reviewed. A subjective scoring system was used to record severity of radiographic valentine shape. Subjective radiographic evidence of left atrial enlargement in a radiographic lateral projection and a final diagnosis based on medical records were also recorded. A total of 81 cats met inclusion criteria. There was a strong positive correlation (P < 0.001) between echocardiographic left atrial size and severity of radiographic valentine shape. There was no effect of echocardiographic right atrial size on the severity of valentine shape, except when concurrent with severe left atrial enlargement. In this situation, right atrial enlargement increased the likelihood of observing a severe valentine shape. There was no effect of right atrial enlargement on the shape of the cardiac silhouette when left atrial enlargement was absent or only mild to moderate. There was no correlation between the category of final diagnosis of cardiac disease and the severity of valentine shape. Findings from this study supported the hypothesis that a valentine-shaped cardiac silhouette in radiographs is due primarily to left atrial enlargement in cats, with right atrial enlargement only impacting the shape if concurrent with severe left atrial enlargement.

Risk factors for incident atrial fibrillation with and without left atrial enlargement in women

Left atrial (LA) enlargement facilitates induction and/or maintenance of atrial fibrillation (AF). However, little is known about risk factors for AF with normal LA size. We prospectively followed 34713 initially healthy women for incident AF. Information on echocardiographic LA size at first AF diagnosis was abstracted from medical charts during AF confirmation. LA enlargement was defined as LA diameter >40 mm. Using a competing risk approach, we constructed Cox proportional-hazards models to calculate hazard ratios (HR) and 95% confidence intervals (CI) of risk factors for incident AF with and without LA enlargement, respectively. Among 796 women with incident AF and available LA size, 328 (41%) had LA enlargement. In multivariable competing risk models, the relationship between age and incident AF was stronger in those with (HR 1.12, 95% CI 1.10-1.14) versus without (HR 1.08, 95% CI 1.06-1.09) LA enlargement (p for difference <0.0001). Body weight was associated with AF only in the presence of LA enlargement (HR per 10 kg 1.34, 95% CI 1.26-1.43; versus 1.07, 95% CI 0.998-1.14, p for difference<0.0001). Hypertension and height were significantly associated with AF both in the presence (HR 1.99, 95% CI 1.49-2.65; and HR per 10 cm 1.36, 95% CI 1.13-1.63) and absence (1.55, 1.25-1.92 and 1.29, 1.10-1.50) of LA enlargement (p for difference 0.17 and 0.66, respectively). These data suggest that LA enlargement explains much of the increased AF risk associated with obesity and age. In contrast, height and hypertension appear to also influence AF risk through other mechanisms besides LA enlargement.

Assessment of Echocardiographic Left Atrial Size: Accuracy of M‐Mode and Two‐Dimensional Methods and Prediction of Diastolic Dysfunction

Despite the American Society of Echocardiography recommendation to use left atrial volume indexed for body surface area (LAVI) for quantification of left atrial size, a variety of methods are used in clinical practice. Our objectives were to evaluate the accuracy of M-mode and two-dimensional (2D) echocardiographic LA size estimates to LAVI and to determine their ability to predict left ventricular diastolic dysfunction. In 150 consecutive patients, LA diameter (LAD), LA diameter indexed for body surface area (LADI), LA area in the apical two- and four-chamber views (LAA 2c and LAA 4c), biplane area-length LA volume (LAV), and LAVI were obtained. The accuracy of these methods to quantify LA enlargement by LAVI, correlation with clinical parameters, and ability to act as a surrogate for diastolic dysfunction were determined using Pearson correlation coefficients along with univariate and multiple logistic analysis. The true degree of LA size (with LAVI as standard) was identified by LAD in 45%, LADI in 42%, LAA 4c in 43%, and LAA 2c in 41%. All methods showed positive correlation with age, E/E', mitral regurgitation, and right atrial size and negative correlation with ejection fraction. LAVI was the strongest method to predict any (c = 0.655, P = 0.012) or moderate-severe (P = 0.856 and P < 0.001) diastolic dysfunction. All methods have greater capacity to identify moderate or severe diastolic dysfunction than any degree of diastolic dysfunction alone. One-dimensional and 2D methods inaccurately quantify LA size and are inferior to LAVI to predict diastolic dysfunction.

Heritability of left atrial size in the Tecumseh population.

Little is known about the determinants of atrial size, and no study has analyzed whether genetic factors are involved in the pathogenesis of LA enlargement. We studied the heritability of echocardiographic left atrial size in 290 parents from the Tecumseh Blood Pressure Study and 251 children from the Tecumseh Offspring Study. All data from the parents and children were obtained at the same field office in Tecumseh, USA. Left atrial dimension was determined echocardiographically in accordance with American Society of Echocardiography guidelines with the use of leading-edge-to-leading-edge measurements of the maximal distance between the posterior aortic root wall and the posterior left atrial wall at end systole. For correlation between the left atrial dimensions of the parents and their offspring, several models were generated to adjust the atrial dimensions in both groups for an increasing number of clinical variables. After removing the effect of age, gender, height, weight, skinfold thickness, and systolic blood pressure, parent-child correlation for left atrial size was 0.19 (P = 0.007). Further adjustment for left ventricular mass and for measuring left ventricular diastolic function increased the correlation to 0.25 (P = 0.001). The present data indicate that heredity can explain a small but definite proportion of the variance in left atrial dimension.

Studies on the Prevalence of Complicated Atrial Arrhythmias, Flutter, and Fibrillation in Patients with Reciprocating Supraventricular Tachycardia Before and After Successful Catheter Ablation

Atrial flutter and AF are complications in approximately 30% of cases of paroxysmal supraventricular tachycardia (PSVT)-indicated catheter ablation, and it is of interest to determine if therapeutic modification for PSVT would eliminate combined atrial tachyarrhythmia like atrial flutter and AF. The aim of this study was to determine the incidence and the risk of atrial tachyarrhythmias after catheter ablation of PSVT. A total of 152 patients (age range 12-74, mean 41 +/- 17 years) with accessory pathway (n = 106) and/or dual atrioventricular nodal conduction (n = 46) were enrolled in a 2-year follow-up program after successful catheter ablation. Possible risks on clinical background (age, sex, PSVT duration, hemodynamic instability during attacks), premature atrial contraction (PACs) on Holter monitoring, echocardiographic left atrial size, and electrophysiological property (insertion site, conduction type, effective refractory period) were evaluated. Atrial flutter and AF were complications in 53 (35%) of the subjects, who were elderly and had a longer PSVT history with a larger left atrial dimension and frequent PACs; however, the electrophysiological properties were similar. After a 2-year follow-up period 36 (24%) of the patients still exhibited PAC runs, including 13 (9%) with atrial flutter and AF, each one of whom were complicated with nonlethal cerebral thromboembolism and congestive heart failure. Multiplelogistic-regression analysis revealed that advanced age (> or = 41 years, P = 0.0152) and frequent PACs (> or = 1% of total daily QRS counts, P = 0.0426) on Holter monitoring are the risk factors of PAC runs and/or atrial flutter and AF. In conclusion, successful ablation for PSVT is thought to be beneficial for preventing atrial flutter and AF. However, careful follow-up to monitor for the recurrence and atrial flutter and AF related complications, especially in patients of solitary atrial flutter and AF without reciprocating tachycardia and with frequent PAC.

Left Atrial Size and the Risk of Stroke and Death

The medical literature contains conflicting reports on the association of left atrial (LA) enlargement with risk of stroke. The relation of LA size to risk of stroke and death in the general population remains largely unexplored. Subjects 50 years of age and older from the Framingham Heart Study were studied to assess the relations between echocardiographic LA size and risk of stroke and death. During 8 years of follow-up, 64 of 1371 (4.7%) men and 73 of 1728 (4.2%) women sustained a stroke, and 296 (21.6%) men and 271 (15.7%) women died. Sex-specific Cox proportional-hazards models were adjusted for age, hypertension, diabetes, atrial fibrillation, smoking, ECG left ventricular (LV) hypertrophy, and congestive heart failure or myocardial infarction. After multivariable adjustment, for every 10-mm increase in LA size, the relative risk of stroke was 2.4 in men (95% CI, 1.6 to 3.7) and 1.4 in women (95% CI, 0.9 to 2.1); the relative risk of death was 1.3 in men (95% CI, 1.0 to 1.5) and 1.4 in women (95% CI, 1.1 to 1.7). Adjusting for ECG LV mass/height attenuated the relation of LA size to stroke and death. After multivariable adjustment, LA enlargement remained a significant predictor of stroke in men and death in both sexes. The relation of LA enlargement to stroke and death appears to be partially mediated by LV mass.

Prevalence and prognostic significance of exercise-induced supraventricular tachycardia in apparently healthy volunteers

The prevalence, characteristics, and prognostic significance of supraventricular tachycardia (SVT) occurring during maximal treadmill exercise testing were examined in 843 male and 540 female asymptomatic volunteers aged 20 to 94 years from the Baltimore Longitudinal Study of Aging who underwent exercise testing a mean or 2.3 times between 1977 and 1991. Exercise-induced SVT occurred during at least 1 test in 51 men (6.0%) and 34 women (6.3%), p = NS for gender. The 85 subjects with exercise-induced SVT were significantly older than the 1,298 free from this arrhythmia (66.0 ± 13.5 vs 49.7 ± 18.0 years, respectively, p < 0.001). The prevalence of SVT increased with age in men (p < 0.001) but not in women. Ninety-eight percent of the 141 discrete episodes of exercise-induced SVT were paroxysmal SVT, with heart rates varying from 105 to 290 beats/min (mean 186.3 ± 43.3); only 16% were > 10 beats in duration and only 4% of subjects were symptomatic. Nearly half (44%) of SVT episodes occurred at peak effort. Coronary risk factors, echocardiographic left atrial size (3.3 ± 6.7 vs 3.3 ± 0.6 cm), and the prevalence of exercise-induced ischemic ST-segment depression (11% vs 13%) were similar in 85 subjects with SVT and 170 control subjects matched for age and sex. Although the incidence of cardiac events (angina pectoris, nonfatal myocardial infarction, cardiac syncope, and cardiac death) was not significantly different between subjects (6%) and control group (10%) over a mean follow-up period of 5.7 ± 3.9 years, 10% of subjects and 2% of controls subsequently developed atrial fibrillation or paroxysmal SVT, p < 0.05 by life-table analysis. Thus, exercise-induced SVT in apparently healthy volunteers is usually limited to short, asymptomatic runs occurring near peak exercise in predominantly older persons, is unassociated with standard coronary risk factors or exercise-induced myocardial ischemia, and does not portend increased cardiovascular mortality or coronary events, but does appear to predict a higher incidence of spontaneous supraventricular tachyarrhythmia over the next several years.

Diagnostic importance of fibrillatory wave amplitude: A clue to echocardiographic left atrial size and etiology of atrial fibrillation

The electrocardiographic fibrillatory wave amplitude in 148 patients with atrial fibrillation was measured. To assess its diagnostic importance in relation to the left atrial size and underlying etiology, M-mode echocardiography was performed on 89 patients. The patients are classified according to the type of atrial fibrillation (paroxysmal or chronic), the f wave amplitude (coarse or fine), and the underlying etiology (rheumatic or nonrheumatic). The average fibrillatory f wave amplitude and echocardiographic left atrial size in chronic and rheumatic atrial fibrillation are significantly greater than in paroxysmal and chronic nonrheumatic patients. Furthermore, the fibrillatory f wave amplitude correlates strongly with the echocardiographic left atrial size.

Responsiveness of Plasma Atrial Natriuretic Factor to Short-Term Changes in Left Atrial Hemodynamics After Percutaneous Balloon Mitral Valvuloplasty

To assess the effect of short-term alteration of left atrial pressure and volume on the circulating plasma level of atrial natriuretic factor, 11 patients with left atrial hypertension due to mitral stenosis were studied at the time of percutaneous balloon mitral valvuloplasty. Hemodynamic measurements and plasma atrial natriuretic factor levels were obtained before, immediately (5 to 10 min) after and 24 h after valvuloplasty, and echocardiographic left atrial size was determined before and 24 h after valvuloplasty. Immediately after valvuloplasty, left atrial pressure decreased from 28 +/- 2 to 10 +/- 1 mm Hg (p less than 0.0005), mitral pressure gradient decreased from 20 +/- 2 to 7 +/- 1 mm Hg (p less than 0.0005), mitral valve area increased from 0.8 +/- 0.1 to 1.9 +/- 0.2 cm2 (p less than 0.0005) and plasma atrial natriuretic factor level rose from 249 +/- 42 to 348 +/- 50 pg/ml (p less than 0.01). This short-term rise in atrial natriuretic factor level may reflect a transient increase in left atrial pressure associated with balloon occlusion of the mitral valve.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic decision-making for replacement surgery in mitral valve prolapse.

The clinical usefulness of M-mode echocardiography for predicting severe mitral regurgitation (MR) requiring valve replacement was assessed in 16 men and 10 women with mitral valve prolapse (MVP) as sole primary cardiac disorder. From left ventricular (LV) angiography, MR was classified as none to moderate (8 cases, group A) or severe (18 cases, group B). At echocardiography, increased LV end-diastolic and end-systolic and left atrial (LA) dimensions, corrected for body-surface area, distinguished group B from group A, with the best validities for LA and LV end-diastolic values. The mean echocardiographic LV fractional shortening and ejection fraction (EF) and the angiographic EF were similar in both groups. Echocardiographic and angiocardiographic LV EF correlated poorly, the former usually overestimating the latter. LV end-diastolic and mean pulmonary capillary wedge pressures were highest in group B, and the latter correlated with echocardiographic LA size. Mitral valve replacement was subsequently performed on 15 of the 18 group B patients. M-mode echocardiography is a valuable adjuvant to clinical assessment of MVP for predicting MR severity and for time-planning of cardiac catheterization or mitral valve surgery.

Restoration and maintenance of sinus rhythm after mitral valve surgery for mitral stenosis

The preoperative clinical, echocardiographic, hemodynamic and surgical data were studied from 40 consecutive patients with pure mitral stenosis and chronic atrial fibrillation who underwent surgical correction of mitral stenosis. After surgery, the patients had cardioversion of atrial fibrillation. The data of 24 patients who maintained sinus rhythm (SR) for more than 3 months (success group) were compared with the data of the 16 patients who failed to maintain SR for more than 3 months (failure group). The patients in the success group were younger (mean age 38 ± 12 vs 47 ± 13 years, p < 0.05), had symptoms for a shorter time (3.0 ± 4.3 vs 6.4 ± 5.0 years, p < 0.02) and had a smaller preoperative echocardiographic left atrial (LA) size (4.9 ± 0.9 vs 5.5 ± 1.0 cm, p < 0.03). The correlation between duration of SR after cardioversion (range 0 to 12 months) and the preoperative data were examined with the use of the “all-possible-subsets-regression” software. The best subset of predictors of successful cardioversion included echocardiographic LA size, functional capacity, duration of symptoms and echocardiographic left ventricular fractional shortening. Patients with symptoms for more than 3 years and echocardiographic LA size of more than 5.2 cm had low rate of successful cardioversion; in this subset of patients, postoperative cardioversion should be avoided.

Reassessment of electrovectorcardiographic signs of left atrial enlargement.

Echocardiographic left atrial size was correlated with 27 electrovectorcardiographic parameters in 93 subjects. In 20 of them hemodynamic studies, including calculation of the left atrial volume, were performed. Subjects were divided into four groups as follows: Group I, 21 healthy subjects; group II, 45 patients with heart disease but no left atrial enlargement; group III, 15 patients with heart disease and left atrial size from 4.1 to 5 cm; and group IV, 12 patients with heart disease and a left atrial size exceeding 5 cm. A good correlation was found between left atrial size and the following parameters: Duration of P wave in standard lead II, voltage of both terminal forces of P wave in lead V1 and its maximal vector in the frontal and sagittal planes. A new index (duration/voltage of P wave in lead II) was postulated, which showed an excellent correlation with left atrial size (p less than 0.001). In all cases the superposition between groups was excessive. These findings indicate the limitations of the classical patterns and raise interest in new parameters concerning the electrocardiographic diagnosis of left atrial enlargement.

Etiologic significance of enlargement of the left atrial appendage in adults.

Fifty-one patients were divided into two groups: 20 patients with proven rheumatic mitral valve disease (RMVD) and 31 patients with left atrial enlargement (LAE) of a nonrheumatic etiology. The latter group included patients with ischemic papillary muscle dysfunction, mitral valve prolapse, and congestive cardiomyopathy. Radiographic studies showed that enlargement of the left atrial appendage (LAAE) was present in 18 of 20 rheumatics but in only one of 31 non-rheumatics. There was no direct relationship between enlargement of the LAA and radiographic or echocardiographic left atrial size, degree of pulmonary venous hypertension (PVH), or presence of atrial fibrillation. It is postulated that rheumatic inflammation of the LAA allows it to dilate out of proportion to the body of the left atrium. In the adult patient with radiographic findings of PVH, LAAE is a valuable and specific radiographic sign of rheumatic mitral valve disease.