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Prediction of left ventricular peak ejection velocity by preceding and prepreceding RR intervals in atrial fibrillation: a new method to adjust the influence between two intervals.

In atrial fibrillation, cardiac performance is dependent on both preceding RR (RR-1) and prepreceding RR (RR-2) intervals. However, relative contributions were not well defined. Left ventricular outflow peak ejection velocity (Vpe) was measured by echocardiography from 21 patients. The relation between RR-1 and Vpe could be divided into two zones; steep slope in short RR-1 intervals (< or =0.5 sec) and plateau in long RR-1 intervals (> 0.5 sec). RR-2 had a weak negative association with Vpe. The mean squared correlation coefficient (r2) between RR-2 and Vpe was 0.15 +/-0.13 and improved to 0.29+/-0.21 (p<0.001), when coordinates with RR-1 < or =0.5 sec were excluded. The RR-1 was positively associated with Vpe. The mean r2 between RR-1 and Vpe was 0.52+/-0.17 and improved to 0.72+/-0.11 (p<0.001), when adjusted by RR-2. Simple linear regression analysis showed that mean RR interval, age, fractional shortening (FS), and mean peak velocity were negatively correlated with modified r2 between RR-2 and Vpe. Multiple stepwise regression analysis revealed that mean RR interval (r2=0.32) and FS (r2=0.16) were significant. In summary, simple modification could improve the relationship of both RR-1 and RR-2 with cardiac performance. RR-2 might play a more role in cardiac performance than previously expected, and when cardiac function was impaired.

Aged↗

Left atrial appendage flow velocity assessment using transesophageal echocardiography in nonrheumatic atrial fibrillation and systemic embolism.

Fifty-four patients with nonrheumatic atrial fibrillation (AF) were studied: 16 patients with (group I) and 38 patients without (group II) documented systemic embolism. Transesophageal echocardiography (TEE) was performed to evaluate the presence of left atrial (LA) appendage thrombus and LA spontaneous contrast, LA size, systolic and diastolic peak velocity of the left pulmonary vein, and forward and backward peak velocity of the LA appendage. No difference was observed in the presence of LA thrombus between the 2 groups. The occurrence of LA spontaneous contrast was significantly (p = 0.01) higher in the group with embolism. LA size, measured by atrial length (4.96 +/- 0.84 vs 4.79 +/- 1.38 cm; p = NS) and atrial width (4.50 +/- 0.96 vs 4.31 +/- 1.24 cm; p = NS), was the same for both groups and thus not associated with embolism. There was no difference in systolic peak velocity (0.39 +/- 0.22 vs 0.44 +/- 0.22 m/s; p = NS), and a trend toward a higher diastolic peak velocity (0.50 +/- 0.17 vs 0.42 +/- 0.15 m/s; p = 0.08) was seen in the left pulmonary vein in the group with embolism. Forward (0.25 +/- 0.19 vs 0.39 +/- 0.23 m/s; p < 0.05) and backward (0.23 +/- 0.15 vs 0.33 +/- 0.16 m/s; p < 0.05) peak velocities of the LA appendage were significantly lower in the embolism group. Assessment of LA appendage flow velocity may potentially identify patients with nonrheumatic AF at high risk for systemic embolism.

Aged↗

Pitfalls in creation of left atrial pressure-area relationships with automated border detection.

Creation of pressure-area relationships (loops) with automated border detection (ABD) involves correction for the variable inherent delay in the ABD signal relative to the pressure recording. This article summarizes (1) the results of in vitro experiments performed to define the range of, and factors that might influence, the ABD delay; (2) the difficulties encountered in evaluating a thin-walled structure like the left atrium in the dog model; and (3) the solutions to some of the difficulties found. The in vitro experiments showed that the ABD delay relative to high-fidelity pressure recordings ranges from 20 to 34 msec and 35 to 57 msec at echocardiographic frame rates of 60/sec and 33/sec, respectively. The delay was not influenced significantly by the type of transducer used, distance from the target area, or size of the target area. The delay in the ABD signal, relative to the echocardiographic image, ranges from nil to less than one frame duration, whereas it is delayed one to two frame durations relative to the electrocardiogram processed by the imaging system. In the dog model, inclusion of even small areas outside the left atrium rendered curves with apparent physiologic contour but inappropriately long delays of 90 to 130 msec. To exclude areas outside the left atrial cavity, time-gain compensation and lateral gain compensation were used much more extensively than during left ventricular ABD recording. By changing the type of sonomicrometers used in our experiments, we were able to record simultaneously ABD and ultrasonic crystal data. However, both spontaneous contrast originating from a right-sided heart bypass pump and electronic noise from the eletrocautery severely interferred with ABD recording.

Animals↗

Successful opacification of the left heart chambers on echocardiographic examination after intravenous injection of a new saccharide based contrast agent.

A new monosaccharide microparticle based echocardiographic contrast agent (SH U 508) was injected intravenously into five healthy male volunteers following which the heart was imaged in an apical four-chamber view. Volumes of 2, 4, 8, and 16 mL of SH U 508 were incrementally injected into each volunteer. Concentrations of 50, 100, 200, 300, and 400 mg microparticles per mL of suspension were used in five successive examinations. Left heart opacification of diagnostic value was obtained during the whole cardiac cycle with concentrations of 300 and 400 mg/mL. There was no interference in imaging of the left ventricular walls due to increased attenuation. SH U 508 showed a good tolerance. No side effect was observed and no clinical relevant changes were observed in the heart rate, blood pressure, ECG, blood chemistry, hematology or urinalysis findings. This new agent may greatly extend the role of cardiac ultrasound and may also permit the examination of the arterial circulation in other organs.

Adult↗

[Renal responses to left atrial stretch in the cat].

The effects of left atrial stretch (LAS) on urine volume (UV), urinary sodium excretion (UNaV) and potassium excretion (UKV) were studied in 50 anesthetized cats. LAS resulted in a marked increase in UV, UNaV and UKV (all P less than 0.001) in the intact animals. Although LAS still caused an increase in UV and UNaV (P less than 0.01) after vagotomy, the increments were significantly less than those in vagi intact animals (P less than 0.005). LAS also induced an increase in UV, UNaV and UKV (P less than 0.05) in the vagi intact cats with heparin infusion (10U/min/kg), but the increments were significantly less than those in the cats without heparin (P less than 0.05). The responses to LAS were abolished by infusion of heparin after vagotomy (P greater than 0.05). Following left renal denervation, the responses to LAS remained unchanged in the innervated kidney, while those in denervated kidney were attenuated, though still significant. The difference in the response between the innervated and the denervated kidneys was statistically significant (P less than 0.05). These results indicate that LAS can induce a marked increase in UV, UNaV and UKV in anesthetized cats through both neural and humoral mechanisms.

Animals↗

B-type natriuretic peptide in organic mitral regurgitation: determinants and impact on outcome.

BACKGROUND: B-type natriuretic peptide (BNP) activation observed in cardiac diseases is a predictor of poor outcome; however, in organic mitral regurgitation (MR), BNP determinants and prognostic value are unknown. METHODS AND RESULTS: We prospectively enrolled 124 patients with chronic organic MR (aged 63+/-15 years, 60% males) in whom we measured BNP level and simultaneously quantified MR degree, left ventricular (LV) remodeling, and left atrial (LA) volumes and analyzed long-term outcome. Baseline BNP level (54+/-67 pg/mL, median 31 pg/mL) was associated univariately with multiple clinical and echocardiographic characteristics, but in multivariate analysis, independent determinants of BNP, beyond age and sex (both P< or =0.01), were LV end-systolic volume index, LA volume, atrial fibrillation, and symptoms (all P<0.02). Conversely, MR degree was not independently associated with BNP. During follow-up, patients with high versus low BNP (> or =31 versus <31 pg/mL) displayed lower survival rates (at 5 years, 72+/-10% versus 95+/-5%, P=0.03) and higher rates of the combined end point of death and heart failure (at 5 years, 42+/-10% versus 16+/-7%, P=0.03). In multivariate analysis, with adjustment for age, sex, functional class, MR severity, and ejection fraction, BNP was independently predictive of mortality (hazard ratio per 10 pg/mL, 1.23 [95% CI 1.07 to 1.48], P=0.004) and of death or heart failure (hazard ratio per 10 pg/mL, 1.09 [95% CI 1.001 to 1.19], P=0.04). CONCLUSIONS: BNP activation in organic MR reflects primarily ventricular and atrial consequences rather than degree of MR. Higher BNP level in patients with organic MR independently predicts adverse events under conservative management. Therefore, BNP activation in organic MR is an emerging biomarker of severity of MR consequences and of poor clinical outcome, and its assessment should be considered in the clinical evaluation and risk stratification of patients with MR.

Aged↗

Benefit of using a triple-lumen catheter to monitor left atrial pressure.

BACKGROUND: Left atrial pressure (LAP) monitoring provides a useful option for management of hemodynamic status in pediatric open-heart surgical patients during the postoperative period. PATIENTS AND METHOD: We used a triple-lumen catheter placed into the left atrium transseptally to measure left atrial pressure. Twenty children that were operated on in our clinic are included in this study: 11 males and nine females. A 5-Fr. triple-lumen radio-opaque polyethylene catheter was used for the procedure. After the repair of the primary cardiac defect, the distal end of the catheter was repositioned transseptally and advanced into the left atrium. The proximal and middle line's distal orifices were left in the right atrium. Distal line was used as a left atrial pressure line, the middle line as a central venous pressure line, and the proximal line as a route for fluid infusion or drug administration. RESULTS: No mortality and no catheter-related complication were observed. No failure or complication occurred during withdrawal of the catheter. CONCLUSION: We conclude that this preliminary technique can be a useful and easy way of monitoring LAP, as well as providing central venous access.

Atrial Function, Left↗

Responses of muscle sympathetic nerve activity to lower body positive pressure.

To evaluate the response of vasomotor sympathetic nerve activity to lower body positive pressure (LBPP), muscle sympathetic nerve activity (MSNA) was microneurographically recorded from the tibial nerve in 10 healthy young men, along with hemodynamic variables and echocardiogram, during exposure to incremental LBPP at 10, 20, and 30 mmHg in the supine position. MSNA was suppressed to a similar extent (27%) at 10- and 20-mmHg LBPP. However, at 30-mmHg LBPP, MSNA tended to increase but was still nearly at the control value. Mean arterial pressure was elevated (11%), total peripheral resistance markedly increased (36%), and stroke volume and cardiac output tended to decrease at 30-mmHg LBPP. Heart rate remained unchanged throughout the procedures. Left atrial dimension significantly increased during 10- and 30-mmHg LBPP, indicating an increased cardiac filling. These results suggest that the inhibitory effect of the cardiopulmonary baroreflex on MSNA at 10- and 20-mmHg LBPP could be counteracted by the sympathoexcitatory effect of the intramuscular pressure-sensitive mechanoreflex at 30-mmHg LBPP. However, the increment of total peripheral resistance at 30-mmHg LBPP may not depend exclusively on this small enhancement of MSNA.

Adult↗

[Detection and surveillance of left atrial thrombosis by transesophageal echocardiography].

Out of 1,141 successive transoesophageal echocardiographic studies performed prospectively between 01/05/1993 and 31/12/1995, 26 cases of left atrial thrombosis were observed (2.2%); 5 were in the left atrium (20%), 19 in the left atrial appendage (73%) and the thrombi were in both atrium and left atrial appendage in 2 cases (7%). The 26 patients included 15 women and 11 men, with an average age of 69 +/- 16 years (range 25-89 years); 22 patients (84%) had permanent atrial fibrillation and 4 were in sinus rhythm. Only 5 of the patients were on oral anticoagulant therapy. All had underlying cardiac disease: 11 mitral valve diseases; 10 dilated cardiomyopathies; 2 hypertrophic cardiomyopathies; 3 other cardiac diseases. The indication for transoesophageal echocardiography was systemic embolism in 13 cases (50%); before D.C. cardioversion in 10 cases (38%) and before percutaneous mitral valvuloplasty in 3 cases. The thrombus was adherent in 18 cases (69%) and mobile in 8 cases (31%). Spontaneous contrast was observed in 23 cases (88%). Intravenous heparin was given as soon as the diagnosis was made. In 4 patients, thrombectomy was indicated in view of the threatening nature of the thrombus and/or the necessity for associated valve replacement. In 22 patients, heparin was relayed by oral anticoagulants on the 10th day of treatment. Control transoesophageal echocardiography was not performed because of the patient's refusal or poor general condition. The other 15 patients were reexamined 1 to 5 times between the 4th day and 12th month: a regression was observed in 13 cases (86%) which was complete in 11 and partial in 2 cases. No cases of embolism occurred during follow-up but six patients died: 1 of the operated cases and 5 of the patients treated medically (3 cardiac failures and 2 cerebral haemorrhages). The authors conclude that left atrial thrombosis is rare in the absence of classical embolic cardiac disease. With the exception of the surgical indication of a life-threatening thrombus and/or associated surgical mitral valve disease, anticoagulant therapy results in complete or partial regression of the thrombus visualised by transoesophageal echocardiography which is essential for follow-up. The prognosis depends on the severity of the underlying heart disease.

Adult↗

Extracorporeal circulation with autogenous oxygenation: hemodynamic and gasometric parameters.

Ten experimental perfusions with autogenous oxygenation were performed in mongrel dogs to evaluate the efficacy of the procedure in maintaining normal hemodynamic the efficacy of the procedure in maintaining normal hemodynamic conditions and adequate blood gases for 1 h. Blood was drained from the right and left atria and pumped to the pulmonary artery and aorta, respectively. Two closed circuits containing compliant chambers and roller pumps were utilized. Artificial ventilation with an FiO2 of 50% were used in 5 animals and with an FiO2 level of 30% in the other 5. EKG, cardiac output, aortic, pulmonary artery, and left atrium pressures were registered. Pulmonary tissue was biopsied after perfusion. The heart was electrically fibrillated after perfusion was established and defibrillated at the end of the bypass. The procedure was able to maintain blood gases and pulmonary, aortic, and left atrial pressures within normal ranges during the perfusion. The mobility of the heart and the access to all coronary arteries was excellent. Clinical central nervous system evaluation, EKG tracings, and pulmonary histological exams showed no adverse effects of perfusion. We conclude that the technique employed may present a suitable proceeding for extracorporeal circulation in closed heart surgeries, and its clinical application should be evaluated as a safe and economical alternative.

Animals↗

Comparison of flecainide and procainamide in cardioversion of atrial fibrillation.

In this prospective, controlled and randomized cross-over study we tried to establish the efficiency and safety of flecainide vs procainamide for the treatment of acute atrial fibrillation. Eighty patients (30 females, 50 males, mean age: 55 +/- 14 years) were included. Patients entered into the study if they had atrial fibrillation of recent onset (< 24 h) with a ventricular rate > 100 beats.min-1 at rest and were < 75 years of age. Exclusion criteria were any sign of heart failure, conduction disturbances, sick sinus syndrome or acute ischaemic events. Randomly 40 patients received flecainide and 40 procainamide as the first treatment. There were no significant clinical difference between the two groups. Procainamide ws given at a dose of 1 g infused over 30 min, and followed by an infusion of 2 mg.min-1 over 1 h. Flecainide was given at a dose of 1.5 mg.kg-1 over 15 min followed by an infusion of 1.5 mg.kg-1 over 1 h. Drug infusion was continued until maximal dose, intolerance or reversion to sinus rhythm. After 1 h of wash out, patients remaining in atrial fibrillation were started on the second drug. Left atrial size was measured by echo. Serum levels of drug and atrial size did not differ between patients who returned to sinus rhythm and those who remained in atrial fibrillation. Conversion to sinus rhythm was achieved in 37 (92%) of the 40 patients treated with flecainide and 25 (65%) of those treated with procainamide (P < 0.001). The time required for reversion to sinus rhythm was similar between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Postfibrillatory enhancement of left atrial contractility after short paroxysms of atrial fibrillation.

Implantable cardioverter defibrillators and pacemakers detect an increasing number of silent episodes of AF. In a porcine model, the study evaluated the contractility of the left atrial appendage (LAA) during AF paroxysms as they may occur in patients. Peak outflow velocity of the LA and mean outflow velocity of the LAA (LAA-V(outmean)) (n = 17) were measured before, during, and after induction of self-terminating AF. LAA-V(outmean) was also measured during incremental pacing from different atrial sites using epicardial Doppler probes (n = 6) and during continuous recordings (n = 5) of 40 minutes of pacing maintained AF. Compared to baseline sinus rhythm, LAA-V(outmean) increased during short AF episodes (41 +/- 3 vs 35 +/- 2 cm/s, P < 0.05). After termination of the AF episodes, LAA-V(outmean) further increased (69 +/- 15 cm/s, P < 0.001 vs baseline). This "postfibrillatory enhancement" maintained after repeated induction of short AF paroxysms. During prolonged AF episodes lasting 40 minutes, an initial hypercontractility (44 +/- 2 vs 38 +/- cm/s, P < 0.01) was followed by a hypocontractility after 20 minutes (29 +/- 12 P < 0.05 vs SR) and a postfibrillatory enhancement after cessation of AF (56 +/- 12 vs 27 +/- 9 cm/s at 40 minutes AF, P < 0.001). L-type Ca channel blockade abolished the initial hypercontractility during AF and the postfibrillatory enhancement. Repetitive AF paroxysms up to 2 minutes did not decrease left atrial contractility. During maintained AF up to 40 minutes an initial hypercontractility and a consecutive hypocontractility, which is overcompensated by a postfibrillatory enhancement of atrial inotropy after cessation of AF, are present. The observed phenomenon seems to be related to an increased Ca(2+) influx through the L-type Ca(2+) channel.

Analysis of Variance↗

Detection of suction and regurgitation of the implantable centrifugal pump based on the motor current waveform analysis and its application to optimization of pump flow.

In this study, a detection algorithm for suction and regurgitation of the centrifugal pump during left heart bypass without relying on external flow or pressure sensors was developed and evaluated in acute studies using adult goats. The detection scheme relies on power spectral density (PSD) analysis of the motor current waveform through which the waveform deformation index (WDI) is obtained. This index is defined as the ratio of the fundamental component of the PSD to the higher PSD components, and its value increases with the deformation of the basic waveform. By assuming that the undistorted motor current waveform can be represented by a pure sine waveform, we theoretically synthesized various waveforms which have different second harmonic components. We were able to synthesize the waveform whose shape was close to the distorted motor current waveform under varying suction levels obtained in a mock loop study. From this study, we came to the conclusion that the WDI value of 0.2 can serve as a threshold level in deciding the suction and regurgitation speeds (rpm) during left heart bypass. In the study using adult goats, we were successful in minimizing both regurgitation and suction when the centrifugal pump speed was adjusted based on the WDI algorithm. The resultant bypass flow ranged from 1.5 to 2.0 L/min which was around 60% of the total flow. Further study is underway to evaluate the applicability of the WDI method in optimizing bypass pump flow.

Algorithms↗

[Long-term left atrial stimulation by transesophageal approach in complicated biventricular infarction].

The authors report the value of transoesophageal pacing in a 50 year old patient with acute biventricular infarction and cardiogenic shock who developed sinus node dysfunction, junctional rhythm and retrograde atrial activation. This mode of pacing was used permanently for a 48 hour period at a rate of 80/min (atrial capture with a pacing potential of 12 volts and an impulse duration of 12 ms). The clinical results were spectacular and the procedure was well tolerated. This technique can be instituted at the bedside and should be considered in selected cases of sinus node dysfunction when endocavitary pacing is not possible.

Atrial Function, Left↗

The effects of heart rate on myocardial velocity and atrio-ventricular displacement during exercise with and without beta-blockade: a tissue Doppler echocardiographic study.

BACKGROUND: Colour tissue Doppler echocardiography (TDE) allows an objective assessment of regional myocardial function. Peak systolic velocity (PSV) and A-V plane displacement (AVPD) obtained from colour TDE correlate well with changes in cardiac wall motion and can discriminate ischemic areas during stress echocardiography. During exercise, the relationship between PSV and AVPD depends on several factors besides ischemia and should be considered when performing exercise stress echocardiography. AIMS: To investigate the relation between PSV, AVPD and heart rate (HR) during semi-upright exercise with and without beta-blockade. SUBJECTS AND METHODS: Twelve healthy men underwent semi-upright exercise stress echocardiography with and without beta-blockade on two separate occasions. Standard echocardiographic projections were used for the stress echocardiography. Grey-scale echocardiographic pictures containing colour TDE information were obtained at rest and during a two-stage exercise test, and the images were analyzed off-line. The PSV and AVPD were measured at four points at the base of the left ventricle at the septum and lateral, inferior and anterior walls. RESULTS: PSV, AVPD and HR gradually increased during exercise. The increases in PSV and AVPD were linearly correlated with the increase in HR. The increases in PSV were significantly lower during exercise with beta-blockade than without beta-blockade (P<0.05). This was not observed in AVPD, as increments were not affected by beta-blockade. CONCLUSION: These data showing a relationship between HR and PSV, and a significantly lower PSV with beta-blockade at a given HR, suggest that PSV is influenced by HR and myocardial contractility, both of which are augmented by physical exercise-induced sympathetic stimulation.

Adrenergic beta-Antagonists↗

Left atrial pressure-clamp servomechanism demonstrates LV suction in canine hearts with normal mitral valves.

A novel technique is presented to study suction of the in situ left ventricle in open-chest experimental animals without requiring cardiopulmonary bypass or disturbing the native mitral valvular apparatus. In 17 dogs, left ventricular pressure (LVP) and left atrial pressure (LAP) were measured, the left atrium was cannulated and connected to a servo pump, and LAP was controlled to a setpoint near 0 mmHg by withdrawing blood from the left atrium. Heart rate [103 +/- 17 (SD) min-1], peak pressure (100 +/- 13 mmHg), minimum pressure (1.4 +/- 0.8 mmHg), and maximum rate of change of pressure with respect to time during isovolumic contraction and relaxation (2,506 +/- 775 and -1,761 +/- 855 mmHg/s, respectively) were normal. Servo control of LAP was possible to +/- 1 mmHg. LV suction was demonstrated in each heart (mean negative LVP -2.3 +/- 1.1 mmHg; P < 0.0001). This new technique demonstrates that the left ventricle can generate negative diastolic suction pressures when examined in vivo and in situ with an undisturbed mitral valve and physiologically normal preload and afterload. This adds to a growing body of evidence that, under appropriate circumstances, the heart can suck blood into itself and thereby aid in its own filling.

Animals↗

Increased volume reduction of late left-atrial emptying for patients with pseudonormal mitral inflow: an analysis for differentiation between normal and pseudonormal mitral inflow.

This study was designed to define the role of left atrial (LA) wall motion during left ventricular (LV) diastolic phase for patients with pseudonormal mitral inflow. We perform the M-mode of posterior aortic, indicating LA, wall motion, and Doppler echocardiography following cardiac catheterization among 71 patients with a ratio of early (E) to late mitral flow (A) >1. The amplitude of total LA wall motion (TM), early LA rapid emptying (EM), and late LA emptying (AM) during the LV diastolic phase were all derived from M-mode analysis. Study patients were classified into two distinct groups according to the LV end-diastolic pressure (EDP): patients with a LVEDP value < 15 mmHg (n = 36, normal group), and patients with a LVEDP value > or = 15 mmHg (n = 35, pseudonormal group). Values of AM (4.7 +/- 1.2 vs 5.5 +/- 1.2 mm) and AM/TM (0.43 +/- 0.07 vs 0.55 +/- 0.08) for the normal and pseudonormal groups, respectively, were significantly higher for the pseudonormal group, whereas EM (6.6 +/- 1.8 vs 4.8 +/- 1.4 mm), TM (11 +/- 3 vs 10 +/- 2 mm), EM/AM (1.41 +/- 0.46 vs 0.91 +/- 0.28), EM/TM (0.58 +/- 0.10 vs 0.48 +/- 0.07) were significantly higher for the normal group. Among these parameters, AM/TM correlated best with the time constant of LV isovolumic relaxation (r = 0.77, P < 0.001). Using an AM/TM ratio value of >0.5 as an indicator of LV diastolic function abnormality, the sensitivity, specificity, positive predictive values, and negative predictive values for the detection of pseudonormalization were 85%, 94%, 94%, and 87%, respectively. These findings suggest that the increased volume reduction of late LA emptying (AM/TM) during LV diastolic phase assessed by M-mode echocardiography is useful for evaluating pseudonormal mitral inflow.

Adult↗

Atrial contraction after surgical isolation of the left atrial posterior wall concomitant with mitral valve replacement.

BACKGROUND: Surgical isolation of the left atrial posterior wall (LA-PW isolation) can terminate chronic atrial fibrillation associated with mitral valve disease. However, atrial contraction after LA-PW isolation has not been evaluated. METHODS AND RESULTS: The study group comprised 14 patients (mean age, 63+/-14 years) with mitral valve disease who recovered and maintained regular sinus rhythm after LA-PW isolation. Before the procedure, and 2-3 weeks and 1 year after the LA-PW isolation, the patients underwent an echocardiographic study. The left atrial (LA) diameter decreased after the LA-PW isolation and the change became significant 1 year later (before: 50.1+/-5.1 mm, after 2-3 weeks: 46.0+/-4.9 mm; p<0.05, after 1 year: 44.0+/-6.1 mm; p<0.05 vs before the operation). The left ventricular (LV) end-diastolic diameter, LV ejection fraction and LV fractional shortening did not change significantly from before the LA-PW isolation and after 1 year. The time - velocity integral of the atrial wave (Ai) and atrial filling fraction significantly increased (Ai: 4.5+/-2.1 cm vs 5.8+/-2.3 cm; p<0.05; atrial filling fraction: 15.4+/-7.7% to 19.2+/-8.3%; p<0.05) during the follow-up period. CONCLUSION: LA-PW isolation can benefit the restoration of regular sinus rhythm and, furthermore, the recovery of atrial contraction.

Aged↗