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PubMed1996

Serial changes of left atrial thrombus in mitral stenosis: transesophageal echocardiographic studies in candidates for balloon mitral commissurotomy.

BACKGROUND: Little is known concerning therapeutic modification of left atrial thrombus in mitral stenosis and its formation after successful balloon valvuloplasty (percutaneous transvenous mitral commissurotomy [PTMC]). OBJECTIVE: To test the roles of the clinical use of anticoagulant therapy and PTMC, serial changes in left atrial thrombus were examined by transesophageal echocardiography in 80 patients with mitral stenosis. RESULTS: No difference in embolic history, New York Heart Association functional class, cardiac rhythm, left atrial size or mitral valve area was found between patients with (n=23) and without (n=57) left atrial thrombus. Diuretic use was the prevalent factor for left atrial thrombi, which were dissolved completely in seven (30.4%) and partially in eight (34.7%) of the patients by adequate warfarin. However, after PTMC (n=53), newly formed thrombus was observed in four of 51 (7.8%) patients, which correlated with left atrial size (at least 50mm), atrial fibrillation and poorly controlled warfarin (thrombo test: 63.8 +/- 18.8% versus 35.9 +/- 17.7%, P<0.005). The newly formed thrombi were dissolved within several weeks. CONCLUSION: Left atrial thrombus in symptomatic mitral stenosis exhibits elusive characteristics and should be strictly monitored even after successful PTMC by transesophageal echocardiography in order to achieve adequate anticoagulation.

Atrial Function, Left↗
PubMed2006

Left atrial emptying fraction correlation with vascular pedicle width in patients with normal systolic function.

OBJECTIVE: To determine the correlation and diagnostic utility of impaired left atrial emptying fraction, an indicator of diastolic dysfunction, with raised intravascular volume determined by vascular pedicle width on upright postero-anterior chest roentgenogram. DESIGN: Cohort study. PLACE AND DURATION OF STUDY: Department of Medicine, King Abdulaziz National Guard Hospital, Alhasa, Saudi Arabia from October till December 2002. PATIENTS AND METHODS: Thirty-two out of 56 patients with normal systolic function (ejection fraction >50%) on echocardiogram were included in the study. Left atrial dimensions were measured at the end of left ventricular diastole (LADed) and systole (LADes) on M-mode tracing. Left atrial emptying fraction (LAEF) was calculated by dividing LADed by LADes. Ratio of peak early diastolic velocity (E/A) to peak late diastolic velocity, isovolemic relaxation time (IVRT) and deceleration time of E-wave (DT) were also recorded on transmitral Doppler signal. Postero-anterior views of chest X-rays done within 48 hours of echocardiogram were studied for the measurement of vascular pedicle width (VPW) and cardiothoracic ratio (CTR). Univariate and multiple regression analysis were performed to identify possible predictors of VPW. Receiver operator curves were constructed to see diagnostic utility of impaired LAEF for raised intravascular volume measured by VPW. RESULTS: Mean age for the patients was 58.56 +/- 17 years. There were 15 females (46.9%) and 17 males (54.1%). LADes, LADed, LAEF and DT were 2.89 +/- 0.63 cm, 3.81 +/- 0.53 cm, 0.75 +/- 0.10 and 202 +/- 49.9 msec respectively. VPW and CTR were 55.81 +/- 10.2 mm and 0.54 +/- 0.08. Significant independent predictors of VPW on univariate regression analysis were entered into multiple regression models, which revealed LAEF and DT as the only predictors of VPW. The final regression equation was VPW = 15.43 + 35.7 (LAEF) + 0.06 (DT), R2 = 0.35, p = 0.0008. LAEF > 0.75 had a sensitivity of 74% and specificity of 94% for diagnosing raised intravascular volume defined as VPW > 53 mm. CONCLUSION: LAEF > 0.75 is a reliable indicator of intravascular volume expansion in patients with normal systolic function signifying diastolic dysfunction and activation of salt and water retaining mechanisms.

Atrial Function, Left↗
PubMed1985

[Occurrence of persistent atrial fibrillation in acquired heart defects].

Functional relationship between hemodynamic overstrain and left-atrial distension was investigated in 209 patients with acquired heart diseases and developing persistent atrial fibrillation. The development of constant atrial fibrillation was shown to depend on the correlation between mean left-atrial pressure and size, and functional relations between the two parameters, i. e. their critical ratio at the time when constant fibrillation is established, were determined. The critical curves which define this relationship for males and females demonstrate that constant fibrillation develops in patients with high mean pressure in the left atrium that is only slightly distended, and in patients with lower mean pressure in a considerably distended left atrium.

Adolescent↗
PubMed1996

The relationship between functional class, pulmonary artery pressure and size in left atrial myxoma.

To examine the correlation between the size of left atrial myxoma, the degree of pulmonary hypertension and the patient's New York Heart Association (NYHA) functional class, the records of 29 surgically treated patients with left atrial myxoma were reviewed. Of 29 patients, 23 were catheterized before surgery. As the preoperative NYHA functional class advanced, the preoperative mean pulmonary artery pressure (mmHg) was seen to increase. Moreover, the weight of the excised myxoma also correlated well with the preoperative pulmonary artery pressure value. In five patients inserted with a Swan-Ganz catheter, the mean pulmonary artery pressure decreased immediately after tumour excision. Postoperatively, the average NYHA class of the 29 patients significantly improved. These results confirmed the positive correlation between the size of the tumour, the pulmonary artery pressure, and NYHA class in patients with left atrial myxoma.

Adult↗
PubMed1986

Neural mechanisms in body fluid homeostasis.

Under steady-state conditions, urinary sodium excretion matches dietary sodium intake. Because extracellular fluid osmolality is tightly regulated, the quantity of sodium in the extracellular fluid determines the volume of this compartment. The left atrial volume receptor mechanism is an example of a neural mechanism of volume regulation. The left atrial mechanoreceptor, which functions as a sensor in the low-pressure vascular system, is located in the left atrial wall, which has a well-defined compliance relating intravascular volume to filling pressure. The left atrial mechanoreceptor responds to changes in wall left atrial tension by discharging into afferent vagal fibers. These fibers have suitable central nervous system representation whose related efferent neurohumoral mechanisms regulate thirst, renal excretion of water and sodium, and redistribution of the extracellular fluid volume. Efferent renal sympathetic nerve activity undergoes appropriate changes to facilitate renal sodium excretion during sodium surfeit and to facilitate renal sodium conservation during sodium deficit. By interacting with other important determinants of renal sodium excretion (e.g., renal arterial pressure), changes in efferent renal sympathetic nerve activity can significantly modulate the final renal sodium excretion response with important consequences in pathophysiological states (e.g., hypertension, edema-forming states).

Afferent Pathways↗
PubMedDate not supplied

Rhythm disturbances in the form of atrial tachycardia in a female patient with polymyositis--a case report.

The presented case report describes a female patient suffering from polymyositis, in whom atrial tachycardia and depressed left ventricular function were diagnosed. Atrial tachycardia was confirmed by electrophysiological study, and the radiofrequency ablation failed to restore sinus rhythm. This case is an example of the tachy phase in brady-tachy syndrome. The patient is evaluated cardiologically on a regular basis with emphasis on bradycardia and asystole episodes because she was symptomatic for many years.

Bradycardia↗
PubMed1997

Comparison of left ventricular function and volumes during transesophageal atrial pacing combined with two-dimensional echocardiography in patients with syndrome X, atherosclerotic coronary artery disease, and normal subjects.

Nine patients with syndrome X were compared with 2 groups of patients known to have coronary artery disease (CAD) (8 patients who developed regional wall motion abnormalities [group ECHO+] and 6 patients who showed only ST depression at echo-pacing [group ECG+]) and with 6 healthy volunteer control subjects. Left ventricular function at rest was normal in all patients. End-diastolic and end-systolic volumes (ml/m2) and ejection fraction were calculated at baseline and at peak of echo-pacing using a Simpson's biplane method. No regional wall motion abnormalities were observed during the echo-pacing in patients with syndrome X or in the volunteers. End-diastolic volume decreased in patients with syndrome X, in the volunteers (from 47 +/- 11 to 30 +/- 12 and from 72 +/- 7 to 38 +/- 6, respectively, p <0.01 for both), and in ECG+ patients (from 48 +/- 10 to 33 +/- 6, p <0.05), whereas it did not change in ECHO+ patients. End-systolic volume decreased in patients with syndrome X and in the volunteers (from 17 +/- 5 to 11 +/- 4 and from 28 +/- 6 to 16 +/- 4, respectively, p <0.01 for both), whereas it did not change or else slightly increased in patients with CAD (from 18 +/- 10 to 16 +/- 5 for ECG+ patients and from 19 +/- 5 to 24 +/- 9 for ECHO+ patients, p = NS for both), regardless of whether regional wall motion abnormalities appeared. Ejection fraction decreased in ECG+ and ECHO+ patients (from 64 +/- 12 to 52 +/- 11 and from 62 +/- 9 to 44 +/- 13, respectively, p <0.01 for both), whereas it did not change in patients with syndrome X and in the volunteers (from 64 +/- 8 to 61 +/- 8 and from 61 +/- 7 to 58 +/- 7, respectively, p = NS for both). During echo-pacing in syndrome X patients no regional wall motion was detected. Left ventricular volumes and ejection fraction showed the same patterns of variation in these patients as they did in the healthy control subjects, in contrast with those patients with CAD, whether or not regional wall motion abnormalities appeared in the latter.

Aged↗
PubMed2001

Left atrial reduction and mitral valve surgery: the "functional-anatomic unit" concept.

The desired outcome for patients undergoing mitral valve surgery includes both good function of the mitral valve, and preservation and restoration of sinus rhythm. To achieve such an outcome, we evolved the concept of the left atrium and mitral valve as a "functional anatomic unit." In this report, we describe a technique for reduction in left atrial size, isolation of the pulmonary veins, and amputation of the left atrial appendage in combination with mitral valve repair. We performed such a procedure in 4 patients, with rheumatic mitral valve disease and chronic atrial fibrillation, with restoration of good valve function and sinus rhythm at 16 to 20 months after surgery.

Adult↗
PubMed1976

An analysis of direct and indirect measurements of left atrial filling pressure.

Left ventricular function may be assessed by direct catheter measurements of left atrial pressure or by indirect measurements of pulmonary artery wedge pressure or pulmonary artery end-diastolic pressure. Controversy exists as to how closely the indirect measurements correlate with true left atrial pressure and to which is the most accurate. To clarify this probelm, we studied 43 patients undergoing cardiac surgical procedures with cardiopulmonary bypass. Both left atrial catheters for direct measurement and Swan-Ganz catheters were placed at the time of surgery. All patients were monitored continuously for 48 hours and hourly measurements were recorded. The resultant 1,620 left atrial pressure and pulmonary artery wedge pressure figures and 1,860 left atrial pressure and pulmonary artery end-diastolic wedge pressure measurements were subjected to computer analysis. The following conclusions have been found: (1) Pulmonary artery wedge pressure is a better indirect measure of left atrial pressure than is pulmonary artery end-diastolic wedge pressure (pooled correlation coefficient 0.629); (2) direct left atrial pressure measurement is more reliable and has fewer complications than indirect measurements; (3) there is no consistent correlation between left atrial pressure and central venous pressure (pooled correlation coefficient 0.3). A discussion of our results and the problems associated with left atrial catheters and Swan-Ganz catheters is presented.

Atrial Function↗
PubMed1997

[Transesophageal echocardiography in the management of patients with atrial fibrillation].

The review evaluates the contribution of transoesophageal echocardiography as to the improvement of management of patients with atrial fibrillation. It emphasises the severity of fibrillation arrhythmia regarding the haemodynamic complications, but especially those arising from embolism causing significant morbidity and mortality, especially in the aged patients with organic heart diseases. An essential improvement in the imaging of the left atrium, but especially of its auricle has enabled a significant progress in the conception of the origin of thromboembolic complications after cardioversion of atrial fibrillation. The detection of thrombi in the left atrial auricle which had until now been impossible, enabled to postpone the patients, by use of transoesophageal echocardiography, for the considered cardioversion, thus reducing the risk of thromboembolism. On the other hand, the transoesophageal examination of the left atrial auricle by use of two-dimensional and doppler echocardiographies has enabled to judge the function of the left atrial auricle not only from the anatomical aspect, but also from that of pathophysiology. This fact enabled to stratify the patients at higher risk of thromboembolism, or vice versa, to select patients appropriate for the planned cardioversion of fibrillation arrhythmia, even if this state has been relatively prolonged. The current knowledge and experience are encouraging and it can be anticipated that within the course of a short period, the transoesophageal echocardiography will play an important role in the management of patients with atrial fibrillation. (Tab. 1, Fig. 3, Ref. 40)

Atrial Fibrillation↗
PubMed1984

Effects of atrial pacing on global and regional left ventricular function in coronary heart disease assessed by digital intravenous ventriculography.

Digital i.v. ventriculography in conjunction with rapid atrial pacing was used to assess the effects of ischemic stress on global and regional function in 22 patients referred for cardiac catheterization (5 had normal coronary arteries and 17 had greater than 70% diameter reduction of at least 1 major coronary artery). End-diastolic, end-systolic and stroke volume indexes and the ejection fraction were determined by an area-length technique from the mask mode images before and after pacing. In addition, segmental responses were quantitated using a radial shortening method. Subjects with normal coronary arteries showed no overall change in the postpacing volume or ejection fraction indexes. Coronary patients showed no overall change in postpacing end-diastolic volume (86 +/- 25 ml/m2 at control vs 90 +/- 31 ml/m2 after pacing, difference not significant), but there was a significant increase in end-systolic volume (25 +/- 15 ml/m2 at control vs 32 +/- 18 ml/m2 after pacing, p less than 0.005) and a decrease in ejection fraction (72 +/- 11% at rest vs 64 +/- 18% after pacing, p less than 0.025). Furthermore, quantitative deterioration in wall motion was seen in 14 of 17 coronary patients (82%) and in none of the normal patients. Analysis of segmental wall motion was the most sensitive diagnostic variable. A combination of atrial pacing stress testing and digital i.v. ventriculography is useful in detecting functionally significant coronary disease through quantitation of global and regional dysfunction which does not require arterial cannulation.

Adult↗
PubMed1993

[Role of transesophageal echography in the study of embolism of cardiac origin].

In the total population, cerebrovascular ischemic diseases account for 0.2-0.3% cases per year, and in the 20-40% of them it is possible to recognize a cardioembolic mechanism. The cardiological examination in patients with stroke is, therefore, aimed at detecting cardiac sources of emboli (left atrial, valvular, and ventricular thrombosis, atherosclerotic plaques of ascending aorta), and at identifying the cardiovascular disease directly or indirectly associated with ischemic stroke. Transesophageal echocardiography (TEE) is particularly suitable for this purpose, due to the proximity of the transducer to the posterior cardiac structures and to its better resolution. Many recent reports have demonstrated that TEE not only improves the recognition of known cardioembolic diseases (intracardiac thrombi, mitral stenosis, valvular prosthesis thrombosis, endocardial infectious diseases), but is also the most reliable non invasive technique suitable to detect atherosclerotic lesions of the ascending aorta. Furthermore, TEE allowed to recognize new anatomic and functional abnormalities, such as left atrial spontaneous echo contrast, atrial septal aneurysm, patent foramen ovale, frequently associated with stroke. Noteworthy, TEE is the only technique suitable for functional and anatomic evaluation of the left atrial appendage. The Authors studied by TEE the functional properties of left atrial appendage in patients with severe mitral stenosis with or without atrial fibrillation, as compared to patients with left atrial thrombosis. Results showed that fractional shortening of left appendage was greatly reduced, at the same extent in the 3 groups, demonstrating that abnormalities in left atrial appendage emptying could be a risk factor for atrial thrombosis. In order to compare TEE with the transthoracic 2D-echo for the detection of cardioembolic sources, the Authors studied 63 patients with ischemic stroke. TEE revealed a possible cardioembolic source in 70% of younger patients and in 50% of patients older than 45 years. These abnormalities were detected by TEE respectively in 10% and in 1.8% of cases. These data are in agreement with many other reports in literature, and suggest the usefulness of TEE in the evaluation of patients with ischemic stroke and no evidence of severe atherosclerotic cerebrovascular disease, in contrast to the poor role of TEE. Another important field is the prevention of stroke in patients at high risk of cardioembolic events. The role of TEE before and immediately after cardioversion in patients with atrial fibrillation has been recently studied by several papers. Cardioversion was proved at low risk of stroke when TEE did not show left atrial or left appendage thrombosis. Therefore, the transesophageal approach identifies patients needing prolonged anticoagulation (roughly 20%), avoiding an undue, potentially dangerous therapy.

Adult↗
PubMed2004

Changes in hematologic markers in patients with mitral stenosis after successful percutaneous balloon mitral valvuloplasty.

Systemic embolism is a major complication of mitral stenosis which is usually related to a presence of left atrial thrombus. Percutaneous balloon mitral valvuloplasty (PBMV) was previously reported to reduce the incidence of this complication. However, the mechanisms of this beneficial procedure was under investigated. The aim of this study was to investigate the changes in coagulation activity, platelet activity and endocardial function in 29 patients with mitral stenosis after successful PBMV. All subjects had good left ventricular systolic function and 48.3% had atrial fibrillation. There was a significant reduction in thrombin-antithrombin complex (TAT) after a successful procedure and the level of thrombomodulin was also significantly higher one month after successful procedure. However, the level of platelet factor 4 (PF4) and beta-thromboglobulin (beta-TG) were increased after this procedure but not achieved the statistical significance. In conclusion, successful PBMV can reduce the prethrombotic state in patients with mitral stenosis. In addition, it may improve endocardial function of the left atrium in those without atrial fibrillation.

Adult↗
PubMed1994

Effect of left ventricular contractile performance on passive left atrial filling--clinical study using radionuclide angiography.

Many invasive and noninvasive methods have been used to study the cardiac atria; however, few allow quantitative measurement of atrial function. To determine the interaction between left ventricular (LV) contraction and left atrial (LA) filling, gated radionuclide angiography was conducted in 30 normal subjects (24 men and 6 women, mean age 58 +/- 10 years, range 26-68). LV and LA time-activity curves and their first-derivative curves were obtained simultaneously by using the method of Bough et al. The LV ejection fraction (64 +/- 18%) and LV peak ejection rate (LVPER; 3.42 +/- 0.27 EDV/s) were computed from these curves. As indices of LA filling, LA fractional emptying (38 +/- 12%) and LA peak filling rate (LAPFR; 2.86 +/- 0.17 LAVmax/s)--the latter being defined as the peak rate of LA filling during the LA filling phase--were also computed from these curves. In all subjects, the timing of the LVPER coincided with the occurrence of LAPFR, and there was a significant positive correlation between the LVPER and LAPFR (r = 0.81, p < 0.001), indicating that the LAPFR was strongly affected by the degree of LVPER. Thus, these results indicate that LV contractile performance plays an important role in determining LA passive filling during ventricular systole.

Adult↗
PubMedDate not supplied

Natural history of hypertrophic cardiomyopathy and aortic thromboembolism in a family of domestic shorthair cats.

A feline domestic shorthair queen and her 3 offspring were all diagnosed with asymptomatic hypertrophic cardiomyopathy (HCM). The family has been followed for 13 years, and 3 cats have died of aortic thromboembolism (ATE). This communication documents the long-term progression of HCM in these cats that presented with mild left ventricular hypertrophy and hyperdynamic systolic ventricular function, developed progressive left atrial enlargement, and eventually resulted in hypodynamic left ventricular systolic function with relative left ventricular chamber dilation at the time of ATE.

Animals↗
PubMed2006

Evaluation of atrial thrombus formation and atrial appendage function in patients with pacemaker by transesophageal echocardiography.

BACKGROUND: Physiologic pacing is claimed to be superior to ventricular pacing in as much as it entails lower risk of atrial fibrillation, stroke, and atrial remodeling. There are few data on the relation between atrioventricular (AV) synchrony and atrial clot formation. Utilizing transesophageal echocardiography (TEE), this study sought to evaluate the effect of AV synchrony loss on left atrial physiology, atrial stasis, and clot formation. METHODS: We conducted a cross-sectional study on patients with both AV and ventricular pacing with left ventricular ejection fraction (LVEF) >30%. TEE enabled us to explore atrial and pacing leads thrombi and measure left atrial appendage (LAA) flow velocity. RESULTS: A total 72 patients (mean age, 65 +/- 11.7) were enrolled in the study. The pacing mode was VVI in 53% and AV sequential in 47% of patients. LVEF (mean +/- SD; %) was 53.3 +/- 6.2% in ventricular pacing mode and 52.2 +/- 6.6 in physiologic pacing mode. Thrombus formation on pacing lead (<10 mm in 97% of patients) was observed in 32% of all the patients (23% in patients with AV sequential pacing mode and 39% with VVI mode). Left atrial appendage flow velocity (LAA-FV) was significantly higher among the patients with AV sequential pacing mode (49.44 +/- 18 cm/s vs 40.94 +/- 19.4 cm/s, P value = 0.02). LAA-FV >40 cm/s was detected in 60% of the patients, 60% of whom were in physiologic mode. Left atrial size was significantly larger among the patients with VVI pacing mode (42.3 +/- 2.3 mm vs 37.79 +/- 4.5 mm, P = 0.001). Multivariate analysis showed no relation between LAA-FV and age, hypertension, diabetes mellitus, left atrial size, and left ventricular function. Only one patient had right atrial clot. There was no thrombus in the ventricles and atrial appendage. CONCLUSION: Long-term loss of AV synchrony induced by VVI pacing is associated with the impairment of LAA contraction. Thrombus formation in the LAA is not increased by VVI pacing in patients with relatively good left ventricular (LV) function and sinus rhythm.

Aged↗
PubMed2004

Plasma B-type natriuretic peptide levels predict postoperative atrial fibrillation in patients undergoing cardiac surgery.

BACKGROUND: Postoperative (postop) atrial fibrillation (AF) occurs in up to 60% of patients after cardiac surgery, leading to longer hospital stays and increased healthcare costs. Recently, B-type natriuretic peptide (BNP) has been reported to predict occurrence of nonpostoperative AF. This study evaluates whether elevated preoperative (preop) plasma BNP levels predict the occurrence of postop AF. METHODS AND RESULTS: One hundred eighty-seven patients with no history of atrial arrhythmia who had a preoperative BNP level and had undergone cardiac surgery were identified. Their records were reviewed, and postoperative ECG and telemetry strips were analyzed for AF until the time of discharge. Postop AF was documented in 80 patients (42.8%). AF patients were older (68+/-11 versus 64+/-14 years, P=0.04), but there was no difference in sex distribution, hypertension, left ventricular (LV) function, LV hypertrophy (LVH), left atrial size, history of coronary artery disease (CAD), or beta-blocker use. Preop plasma BNP levels were higher in the postop AF patients (615 versus 444 pg/mL, P=0.005). After adjustment for age, sex, type of surgery, hypertension, LV function, LVH, left atrial size, CAD, and beta-blocker use, the odds ratios of postop AF according to increasing quartiles, compared with patients with lowest quartile, were 1.8, 2.5, and 3.7 (P(trend)=0.03). CONCLUSIONS: An elevated preop plasma BNP level is a strong and independent predictor of postop AF. This finding has important implications for identifying patients at higher risk of postop AF who could be considered for prophylactic antiarrhythmic or beta-blocker therapy.

Aged↗
PubMed2003

Atrial compartment operation for atrial fibrillation: to isolate the left atrium or not?

BACKGROUND: The atrial compartment operation was designed to convert atrial fibrillation (AF) to sinus rhythm with intentional preservation of the electrical connection between adjacent atrial compartments. However, incidental left atrial isolation was observed in some patients. This study compared the long-term clinical outcomes of left atrial isolation for AF with those with right and left atrial connection. METHODS: Twenty patients with mitral valve disease and chronic AF who underwent atrial compartment operation with successful sinus conversion were studied. Left atrial isolation was documented by local electrogram recording. When there were no signs of electrical connection between the left atrium and the rest of the heart, either during sinus rhythm or during stimulation from various atrial compartments, left atrial isolation was confirmed. All patients were followed by electrocardiogram and echocardiogram serial recordings. Clinical signs and symptoms of cardiac performance and thromboembolism were also examined. RESULTS: Seven patients showed an isolated left atrium and 13 patients had electrical connection between the right and left atria. The age, gender, AF duration, and underlying disease were not different between the two groups of patients. During a mean follow-up period of 66 +/- 15 months, none of the patients with left atrial isolation showed recurrence of AF, although one experienced paroxysmal atrial flutter. However, 8 of the 13 patients with right and left atrial connection experienced recurrent atrial flutter/fibrillation (6 atrial flutter and 5 AF) (p = 0.058). The propensity for recurrent atrial flutter/fibrillation in these patients may be related to the conduction delay between the two atrial compartments, measured at 142 +/- 48 ms. At the end of the follow-up period, all patients with left atrial isolation remained in normal sinus rhythm without antiarrhythmic drugs. Of the patients who had right and left atrial connection, 2 developed sustained AF and 1 developed atrial flutter. Patients with left atrial isolation showed a decreased transmitral "A" flow compared with those with right and left atrial connection. Postoperative left atrial diameter and clinical functional class did not differ between patients with and without left atrial isolation. The incidence of embolization observed in both treatment groups did not differ significantly: 14% (1/7) in patients with left atrial isolation and 8% (1/13) in patients with right and left atrial connection (p > 0.05 between the groups). CONCLUSIONS: Left atrial isolation confers a better arrhythmia outcome but at the expense of poorer mechanical performance as compared with preserved electrical connection between the two atria. Nonetheless, all patients remain at risk for systemic embolization. Therefore, modifications of current surgical incisions for AF are needed.

Adult↗