Transmitral A-wave Velocity Research Articles

Effect of mitral valve transcatheter edge-to-edge repair on indices of left atrial performance in chronic mitral regurgitation.

Effect of transcatheter edge-to-edge repair (TEER) using MitraClip in patients with mitral regurgitation (MR) on left atrial (LA) kinetic energy (LAKE), an index of LA work, and LA strain, a measure of LA performance, have not been well defined. Patients with chronic primary or secondary 3+ or 4+ MR were analyzed pre- and post-TEER using MitraClip. LAKE was determined by echocardiography using LA stroke volume and A-wave velocity. Peak atrial longitudinal strain (PALS), peak atrial strain in early diastole, and peak atrial contraction strain (PACS) were obtained by speckle tracking echocardiography. Thirty-nine patients undergoing TEER with MitraClip were screened, 12 met criteria for analysis (9 primary and 3 secondary MR). Compared to pre-TEER, there was a significant increase post-TEER in LAKE (71.0±64.1vs. 177.5±167.9 dyne·cm·103 , respectively; p=.008) and Doppler transmitral A-wave velocity (87.8±41.4vs. 138.5±43.7cm/s, respectively; p<.001); LA stroke volume did not change significantly. Mitral valve mean gradient significantly increased post-TEER compared to pre-TEER (5.7±2.1vs. 3.3±2.1mmHg, respectively; p=.01). There was a trend toward decrease in PALS post-TEER compared to pre-TEER (16.2±4.8vs. 20.7±9.9%, respectively; p=.05). Peak atrial strain in early diastole significantly decreased post-TEER compared to pre-TEER (7.2±3.0vs. 14.1±7.2%; respectively, p<.001), while PACS did not significantly change (9.1±3.5vs. 6.7±5.2%, respectively; p=.07). In patients with chronic MR, LAKE increases after TEER with MitraClip driven by an increase in LA emptying velocities. Changes were also seen in LA strain with MitraClip. These procedurally induced changes due to mild mitral stenosis may have clinical implications.

Left atrial appendage preservation versus closure during surgical ablation of atrial fibrillation

ObjectiveThere is limited evidence regarding the effectiveness of left atrial appendage (LAA) closure during surgical ablation of atrial fibrillation (AF) in yielding superior clinical outcomes. This study aimed to evaluate...

P183 Arterial stiffness was inversely associated with left ventricular diastolic function in indigenous Papuan populations

Abstract Background Age-related increase in systolic pressure is known to be absent in indigenous Papuan populations, partially because of their life-long low-sodium and high-potassium diets. Purpose The aim of this study was to investigate the age-related change in left ventricular (LV) systolic and diastolic function and the relationship with arterial hemodynamics among the indigenous Papuan highland people. Methods Indices of arterial hemodynamics were measured using oscillometric brachial cuff-based sphygmomanometer (Mobil-O-Graph). Brachial-ankle pulse wave velocity (baPWV) was measured using a semiautomatic device (form ABI/baPWV). LV systolic and diastolic function was evaluated by 2-dimensional echocardiography and tissue-Doppler imaging using Vivid iq. Results A total of 81 native Papuans (median age 42 years, 47% women) were enrolled in this study. None of the subjects took any medicines, particularly antihypertensive drugs. All participants presented in sinus rhythm. With ageing, LV mass index remained unchanged, and LV ejection fraction increased, but mildly reduced (40–50%) in 3 participants. Transmitral E-wave velocity slightly decrease but the change was not significant. Transmitral A-wave velocity markedly increased (ρ=0.60, P &amp;lt; 0.001) and E/A ratio decreased with age (ρ=-0.52, P &amp;lt; 0.001). Age-related change of E-wave deceleration time was not significant. Septal e′ (ρ=-0.60, P &amp;lt; 0.001) and lateral e′ decreased (ρ=-0.53, P &amp;lt; 0.001) and average E/e′ increased with age (ρ=0.44, P &amp;lt; 0.001). Left atrial volume index did not change significantly with age. In multivariate regression analysis, baPWV was independently associated with E/e" ratio both before and after adjustment for age, sex, body mass index, mean arterial pressure, and heart rate; however, indices of wave reflection including augmentation index and reflection magnitude were not associated with E/e′. Only age and heart rate were inversely associated with E/A ratio. Conclusion LV systolic function was preserved in indigenous Papuan populations; however, LV diastolic function decreased with ageing. Age-related arterial stiffening, not wave reflection, was inversely related to LV diastolic function.

Predictive value of transmitral A‐wave acceleration time for paroxysmal atrial fibrillation

It has been shown that transmitral A-wave (TMAW) is affected in paroxysmal atrial fibrillation (PAF), and decreased left atrial contractions cause a decrease in the TMAW velocity. The relationship between TMAW acceleration time (TMAW-AccT) and PAF is unknown. In this study, the predictive value of TMAW-AccT for PAF was investigated. Seventy PAF patients (mean age: 57.8±11.0years) and 70 control patients (mean age: 58.1±10.5years) were included in the study. Transthoracic echocardiography was performed in sinus rhythm in all patients. For TMAW-AccT, the time between the basal point of the A-wave and the highest point reached was measured. Transmitral A-wave -AccT was significantly longer in the PAF group than the control group (TMAW-AccT; 88.5±18.1 vs 77.2±16.4ms, P=.000, respectively). The left atrial diameter and the left atrial volume index were similar between the groups (P=.07, P=.18, respectively). According to a multivariate logistic regression analysis, the TMAW-AccT (OR: 1.02, 95% confidence interval 1.02-1.07, P<.001) was a predictor of PAF. A receiver operating characteristic curve analysis showed a cutoff value of TMAW-AccT of >82ms (sensitivity: 65.7%, specificity: 64.3%, positive predictive value: 64.8%, negative predictive value: 65.2%). Transmitral A-wave-AccT can be used as an early marker in detecting PAF without dilated left atrium.

Reduced trans-mitral A-wave velocity predicts the presence of wild-type transthyretin amyloidosis in elderly patients with left ventricular hypertrophy.

Wild-type transthyretin amyloidosis (ATTRwt) is often overlooked in elderly patients with left ventricular hypertrophy (LVH). Impaired atrial function, in addition to ventricular diastolic dysfunction, is one of the hallmarks of cardiac amyloidosis. Here, we assessed the hypothesis that atrial function evaluated by A-velocity in pulse Doppler echocardiography is useful to differentiate ATTRwt in elderly patients with LVH. We analyzed 133 consecutive patients who underwent tissue biopsy to rule out infiltrative cardiomyopathy in our institute. We excluded patients younger than 50years, without LVH (LV thickness was less than 12mm), with other types of cardiac amyloidosis and patients with chronic atrial fibrillation, and analyzed remaining 51 patients (ATTRwt: 16, non-ATTRwt: 35). ATTRwt patients were significantly older and had advanced heart failure compared with non-ATTRwt group. In echocardiography, E/A, E/e', and relative wall thickness was significantly higher in ATTRwt group than non-ATTRwt group. A-velocity was significantly decreased in ATTRWT group compared with non-ATTRwt group (40.8±20.8 vs. 78.7±28.2cm/s, p=0.0001). Multivariate logistic analysis using eight forced inclusion models identified trans-mitral Doppler A-wave velocity was more significant factor of cardiac amyloidosis in ATTRwt. In receiver operating characteristic (ROC) analysis, the area under the curve (AUC) for A-wave velocity in discrimination between ATTRwt and non-ATTRwt were 0.86 (CI 0.76-0.96, p<0.001). The cut-off value was 62.5cm/s, and it yielded the best combination of sensitivity (69.7%) and specificity (87.5%) for prediction of amyloidosis. We concluded that reduced A-velocity predicts the presence of ATTRwt in elderly patients with LVH in sinus rhythm.

Left Atrial Appendage Resection Versus Preservation During the Surgical Ablation of Atrial Fibrillation

Left atrial appendage (LAA) resection during the Maze procedure may decrease thromboembolic risks, but its preservation may improve left atrial contractile function. This study compared the clinical effects of LAA resection and preservation after the Maze procedure. A retrospective review was made of 379 patients (mean age 53.3 ± 12.6 years, 244 females) who underwent the cryo-Maze procedure in conjunction with mitral surgery from 1999 to 2011. The LAA was resected in 187 patients (resection group) but preserved in 192 patients (preservation group). Outcomes were compared using a propensity score study design based on 20 baseline characteristics to obtain well-matched patient pairs. Propensity score matching yielded 119 pairs of patients in whom there were no significant differences in baseline profiles between the two groups. During a mean follow-up of 3.1 ± 2.8 years, there were 16 deaths, 6 cases of stroke, and 39 cases of atrial fibrillation recurrence. There were no significant differences in stroke-free survival (p = 0.88) and freedom from AF while off antiarrhythmic drugs (p = 0.46) between the two groups. On serial echocardiographic assessments, patients in the preservation group showed a higher transmitral A-wave velocity (peak atrial contraction wave velocity; p = 0.47, 0.020, and 0.001 at 3, 6, and 12 months, respectively) and lower E/A ratio (peak early filling wave [E-wave] velocity / A-wave velocity; p = 0.34, 0.065, and 0.001 at 3, 6, and 12 months, respectively) at each timepoint compared with the resection group. Preservation of the LAA during the Maze procedure resulted in similar clinical and rhythm outcomes, but LA contractile function superior to that of LAA resection.

Transforming growth factor β1-mediated atrial fibrotic activity and the recovery of atrial mechanical contraction after surgical maze procedure

BackgroundThe maze procedure for atrial fibrillation (AF) is effective in restoring sinus rhythm; however, a significant proportion of patients failed to recover atrial mechanical contraction (AMC). We hypothesized that preoperative atrial fibrotic activity would be related to the AMC recovery. MethodsIn atrial tissues of 128 consecutive patients who underwent mitral valve and combined maze surgery using cryoablation for persistent AF, preoperative mRNA levels of various biomarkers were measured including transforming growth factor-β1 (TGF-β1), atrial natriuretic peptide, brain natriuretic peptide (BNP), C-reactive protein, connective tissue growth factor, matrix metalloproteinase, N-terminal prohormone BNP, and tissue inhibitor of metalloproteinase. Presence of AMC was assessed using Doppler echocardiographic measurement of the transmitral A-wave velocity. ResultsAt 1-year follow-up, patients without AMC (n=62) showed higher preoperative TGF-β1 mRNA expression (0.42 versus 0.28, P=0.01) than those with AMC (n=66). There was no significant difference between the two groups regarding the other biomarkers. Recovery rate of AMC and the increment of A-wave velocity were reduced with the increase of preoperative TGF-β1 mRNA level. Multiple logistic regression analysis revealed that TGF-β1 mRNA levels were independently associated with the absence of AMC (odds ratio 7.47, 95% CI 1.63 to 34.4, P=0.01). ConclusionsTGF-β1-mediated atrial fibrotic activity might exert a detrimental effect on the reversibility of atrial mechanical contraction after the maze and combined mitral valve surgery for long-standing persistent AF. Earlier surgical intervention might be needed to preserve atrial mechanical function.

Atrial TGF-β1 Expression and Recovery of Atrial Contraction after Maze Procedure

Background: The maze procedure for atrial fibrillation (AF) is effective in restoring sinus rhythm, however, significant proportion of patients failed to recover atrial mechanical contraction (AMC). We hypothesized that preoperative level of atrial transforming growth factor-β1(TGF-β1) mRNA expression would be related to recovery of AMC. Methods and Results: Preoperative atrial TGF-β1 mRNA was measured in 128 consecutive patients who underwent the mitral valve surgery combined with maze procedure with cryoablation for persistent AF. Presence of AMC was assessed using Doppler echocardiographic measurement of the transmitral A-wave velocity. At one year follow-up, patients without AMC (n=62) had higher levels of atrial TGF-β1 mRNA expression (P=0.01) and more extensive atrial fibrosis than those with AMC (n=66). When the patients were divided into 3 groups according to the TGF-β1 mRNA level, the recovery rate of AMC and the increment of A-wave velocity gradually decreased from the lowest to the highest patient group. Multiple logistic regression analysis revealed that TGF-β1 mRNA level was independently associated with the postoperative absence of AMC (odd ratio 7.47, 95% CI 1.63–34.4, P=0.01). Conclusions: Atrial TGF-β1 mRNA expression was significantly associated with no recovery of atrial mechanical activity one year after the maze procedure using cryoablation.

Long-Term Effects of the Maze Procedure on Atrial Size and Mechanical Function

The Maze procedure is effective in restoring sinus rhythm, but the extensive procedure may have negative effects on atrial mechanical function. Decreased atrial contractility has been observed early after the Maze procedure. The purpose of this study was to determine the long-term effect of the Maze procedure on atrial size and mechanical function. Fifty-two patients with symptomatic atrial fibrillation, without structural heart or valvular disease, underwent the Cox Maze III procedure. Atrial size and mechanical function were assessed by echocardiographic examination at baseline and postoperatively at a mean +/- SD of 6 +/- 1 and 56 +/- 12 months. The left atrial area was decreased 6 months after the procedure compared with baseline (mean, 15.4 +/- 3.3 vs 17.6 +/- 3.2 cm2, p < 0.01). By 56 months, however, the left atrial area had increased compared with the 6-month follow-up (19.5 +/- 3.9 vs 15.4 +/- 3.3 cm2, p < 0.001), resulting in no difference in left atrial size compared with the baseline values. The left atrial contractility, measured as fractional area change, was significantly reduced at 6 and 56 months of follow-up (0.20 +/- 0.09 and 0.19 +/- 0.07 vs baseline 0.36 +/- 0.09), as was the transmitral A-wave velocity (30 +/- 12 and 28 +/- 8 cm/s vs baseline 40 +/- 15). The same pattern was seen for the right atrium. This study shows that the Maze procedure results in a sustained decrease in atrial contractility. The initial reduction in atrial size is later reversed. These findings contradict late improvements in atrial mechanical function after Maze surgery and may have important implications for the risk of thromboembolic complications.

Atrial fibrillation surgery simplified with cryoablation to improve left atrial function

Background. The Maze procedure restores atrial fibrillation to normal sinus rhythm. However, concurrent left atrial functional recovery is not always achieved. To address this limitation, a modification using linear cryo-ablation is described. Methods. Between July 1997 and December 1999, 83 patients received atrial fibrillation surgery in association with mitral valve surgery with or without additional concurrent procedures by either the conventional technique, group I (n = 30) or the modified technique, group II (n = 53). Onset of sinus conversion and echocardiographic assessment of postoperative left ventricular function, left atrial size, and mitral A-wave velocity were compared in the early postoperative period and 6 months after surgery. Results. Sinus conversion occurred significantly earlier in group II, 2.4 ± 5 days versus group I, 7.0 ± 10 days. The mean transmitral A-wave velocity and the incidence of A-wave appearance in the early postoperative period and 6 months postoperatively were greater in group II than group I. Conclusions. With the current modification, restoration of sinus rhythm and superior left atrial contractile function occurred earlier than with the standard Maze III technique.

Noninvasive assessment of left ventricular end-diastolic pressure by the response of the transmitral a-wave velocity to a standardized valsalva maneuver

Impaired relaxation is frequently masked by elevated filling pressures, resulting in a pseudonormal flow pattern (E/A >1.0). Because the E/A wave ratio increases as filling pressures rise, it is generally assumed that patients with an E/A ratio of <1.0 (impaired relaxation pattern) have relatively low filling pressures. Nevertheless, patients with an E/A ratio of <1.0 can have as profoundly elevated filling pressures as patients with a pseudonormal or restrictive filling pattern. Because left ventricular (LV) pressure during end-diastole essentially determines atrial afterload, the response of the A-wave velocity to a reduction of atrial afterload by a standardized Valsalva maneuver should allow estimation of LV end-diastolic pressure (LVEDP) regardless of the baseline Doppler flow pattern. This was tested in 20 consecutive patients who were studied by pulse-wave Doppler echocardiography during cardiac catheterization. There was a close correlation between LVEDP and the change in A-wave velocity during the Valsalva maneuver (r = 0.85, SEE 6.7 mm Hg) regardless of the baseline E/A ratio. In patients with a LVEDP of <15 mm Hg the A wave decreased by 21 ± 15 cm/s. In patients with a LVEDP of >25 mm Hg the A wave increased by 18 ± 13 cm/s. The change in the E/A ratio during Valsalva correlated fairly with LVEDP (r = −0.72, SEE 8.8 mm Hg), the baseline E/A ratio correlated poorly, and scatter was substantial (r = 0.46, SEE 11.2 mm Hg). Just as elevated filling pressures can mask impaired relaxation, the impaired relaxation pattern can mask the presence of elevated filling pressures. This can be revealed by testing the response of the A wave to the Valsalva maneuver, allowing estimation of LVEDP independent of the baseline E/A ratio.

Assessment of left atrial appendage function after cardioversion of atrial fibrillation: Relation to left atrial mechanical function

Although several flow patterns in the left atrial appendage have been described, mechanical determinants of its function have not been elucidated in human beings. We attempted to investigate changes in left atrial appendage function after cardioversion of atrial fibrillation and examine the potential relation between appendage function and left atrial mechanical function. Twenty patients without mitral valvular disease underwent transesophageal and transthoracic echocardiography at 24 hours and 1 week after cardioversion of atrial fibrillation. Left atrial appendage function was assessed by the pulsed Doppler measurements of left atrial appendage emptying and filling velocities corresponding to early and late ventricular diastole, respectively. Left atrial mechanical function was evaluated by the transmitral A-wave velocity, percent atrial contribution of the total left ventricular filling (percent atrial filling), and the pulmonary venous A-wave velocity. Left ventricular function was also estimated with conventional M-mode echocardiography. The late appendage emptying and filling velocities markedly increased during 1 week after cardioversion ( p < 0.0001, respectively). This finding was associated with an increase in left atrial mechanical function. Changes in the late emptying and filling velocities significantly correlated with changes in the transmitral A-wave velocity ( r = 0.59, p < 0.01), percent atrial filling ( r = 0.61, p < 0.005), and the pulmonary venous A-wave velocity ( r = 0.56, p < 0.05). In contrast, little change was observed in the early emptying and filling velocities. There was no relation between the indexes of left ventricular function and those of appendage function. In conclusion, unless there was an alteration of the loading conditions, left atrial appendage function improved over several days after cardioversion, and its function was related to left atrial mechanical function. (Am Heart J 1998;135:1020-6.)

Evaluation of the effect of transthoracic cardioversion from ventricular tachycardia to sinus rhythm on left atrial mechanical function

We measured left atrial function during sinus rhythm before and after VT was induced in an electrophysiology laboratory, using peak transmitral A-wave velocity from pulsed-Doppler transthoracic echocardiography as a marker of left atrial mechanical function. The results of this prospective study do not support the hypothesis that a transthoracic shock of mild to moderate energy diminishes atrial mechanical function.