Left atrial strain parameters to predicting elevated left atrial pressure in patients with atrial fibrillation.

OBJECTIVES: To assess the ability of left atrial (LA) strain parameters to discriminate patients with elevated left atrial pressure (LAP) from patients with atrial fibrillation (AF). METHODS AND RESULTS: A total of 142 patients with non-valvular AF who underwent first catheter ablation (CA) between November 2022 and November 2023 were enrolled in the study. Conventional and speckle-tracking echocardiography (STE) were performed in all patients within 24 h before CA, and LAP was invasively measured during the ablation procedure. According to mean LAP, the study population was classified into two groups of normal LAP (LAP < 15 mmHg, n = 101) and elevated LAP (LAP ≥ 15 mmHg, n = 41). Compared with the normal LAP group, elevated LAP group showed significantly reduced LA reservoir strain (LASr) [9.14 (7.97-11.80) vs. 20 (13.59-26.96), p < .001], and increased LA filling index [9.60 (7.15-12.20) vs. 3.72 (2.17-5.82), p < .001], LA stiffness index [1.13 (.82-1.46) vs. .47 (.30-.70), p < .001]. LASr, LA filling index and LA stiffness index were independent predictors of elevated LAP after adjusted by the type of AF, EDT, E/e', mitral E, and peak acceleration rate of mitral E velocity. The receiver-operating characteristic curve (ROC) analysis showed LA strain parameters (area under curve [AUC] .794-.819) could provide similar or greater diagnostic accuracy for elevated LAP, as compared to conventional echocardiographic parameters. Furthermore, the novel algorithms built by LASr, LA stiffness index, LA filling index, and left atrial emptying fraction (LAEF), was used to discriminate elevated LAP in AF with good accuracy (AUC .880, accuracy of 81.69%, sensitivity of 80.49%, and specificity of 82.18%), and much better than 2016 ASE/EACVI algorithms in AF. CONCLUSION: In patients with AF, LA strain parameters could be useful to predict elevated LAP and non-inferior to conventional echocardiographic parameters. Besides, the novel algorithm built by LA strain parameters combined with conventional parameters would improve the diagnostic efficiency.

Interatrial Shunt Devices.

Elevated left atrial pressure during exercise is a hallmark of heart failure (HF) and is associated with adverse left atrial remodeling and poor outcomes. To decompress the pressure-overloaded left atrium in patients with HF, several device-based approaches have been developed to create a permanent, pressure-dependent, left-to-right interatrial shunt. Such approaches are currently in various stages of investigations in both HF with reduced ejection fraction (EF) and HF with preserved EF. This review discusses the evolution of the concept of left atrial decompression and summarizes the current landscape of device-based approaches used for left atrial decompression.

Society of thoracic surgeons risk score and left atrial pressure for predicting clinical outcomes among transcatheter mitral edge-to-edge repair patients.

BACKGROUND: Limited data exist regarding the performance of the Society of Thoracic Surgeons (STS) risk score among transcatheter mitral edge-to-edge repair (TEER) patients. OBJECTIVE: Evaluate STS score accuracy, and the incremental value of post-procedural left atrial pressure (LAP). METHODS: A retrospective analysis of TEER patients between 2013 and 2020. Patients were allocated into 3 groups: high (≥8% [n = 298, 31%]), intermediate (4%-8% [n = 318, 33%]), and low (<4% [n = 344, 36%]). Primary outcomes included 1-year mortality or cardiovascular hospitalizations. Cox proportional hazards regression modeling was used to determine the hazard ratio of the primary outcome, and STS score accuracy was assessed by receiver operating characteristic. A spline curve was used to display the relationship between LAP and the primary endpoint. Continuous net reclassification improvement (NRI) was used to determine the incremental value of LAP. RESULTS: We included 960 patients, primarily elderly (79 [70-85]), with a median STS risk of 5.6 (3-9). High-risk patients were older (83 [75-89], 81 [74-87], 72 [64-79], p < 0.001), and had more comorbidities compared to intermediate and low-risk groups. Upon Cox regression, STS score (high vs. low: HR 2.5 [1.7-3.8]; Intermediate vs. low: HR 1.8 [1.2-2.7] and LAP HR 1.03 [1.01-1.06], p = 0.007) were associated with the outcome. C statistics analysis revealed low accuracy of the STS score (AUC-0.61 [0.58-0.65, p < 0.001]). Continuous NRI analysis indicated an improvement in risk prediction of 17% (6.9-26.2), p < 0.001. CONCLUSION: STS risk score has low accuracy in predicting clinical outcomes after TEER. Adding LAP measurements can improve reclassification and identify those prone to adverse outcomes.

Predictors of hemodynamic response to mitral transcatheter edge-to-edge repair.

BACKGROUND: Improvement in left atrial pressure (LAP) during transcatheter edge-to-edge repair (TEER) is associated with improved outcomes. We sought to investigate the predictors of optimal hemodynamic response to TEER. METHODS: We identified patients who underwent TEER at Mayo Clinic between May 2014 and February 2022. Patients with missing LAP data, an aborted procedure, and those undergoing a concomitant tricuspid TEER were excluded. We performed a logistic regression analysis to identify predictors of optimal hemodynamic response to TEER (defined as LAP ≤ 15 mmHg). RESULTS: A total of 473 patients were included (Mean age 78.5 ± 9.4 years, 67.2% males). Overall, 195 (41.2%) achieved an optimal hemodynamic response after TEER. Patients who did not achieve an optimal response had higher baseline LAP (20.0 [17-25] vs. 15.0 [12-18] mmHg, p < 0.001), higher prevalence of AF (68.3% vs. 55.9%, p = 0.006), functional MR (47.5% vs. 35.9%, p = 0.009), annular calcification (41% vs. 29.2%, p = 0.02), lower left ventricular EF (55% vs. 58%, p = 0.02), and more frequent postprocedural severe MR (11.9% vs. 5.1%, p = 0.02) and elevated mitral gradient >5 mmHg (30.6% vs. 14.4%, p < 0.001). In the multivariate logistic regression analysis, AF (OR = 0.58; 95% CI = 0.35-0.96; p = 0.03), baseline LAP (OR = 0.80; 95% CI = 0.75-0.84; p < 0.001) and postprocedural mitral gradient <5 mmHg (OR = 0.35; 95% CI = 0.19-0.65; p < 0.001), were independent predictors of achieving an optimal hemodynamic response. In the multivariate model, residual MR was not independently associated with optimal hemodynamic response. CONCLUSIONS: Optimal hemodynamic response is achieved in 4 in 10 patients undergoing TEER. AF, higher baseline LAP, and higher postprocedural mitral gradient were negative predictors of optimal hemodynamic response after TEER.

Left atrial expansion index measured with cardiovascular magnetic resonance estimates pulmonary capillary wedge pressure in dilated cardiomyopathy.

BACKGROUND: Pulmonary capillary wedge pressure (PCWP) assessment is fundamental for managing dilated cardiomyopathy (DCM) patients. Although cardiovascular magnetic resonance (CMR) has become the gold-standard imaging technique for evaluating cardiac chamber volume and function, PCWP is not routinely assessed with CMR. Therefore, this study aimed to validate the left atrial expansion index (LAEI), a LA reservoir function parameter able to estimate filling pressure with echocardiography, as a novel CMR-measured parameter for non-invasive PCWP estimation in DCM patients. METHODS: We performed a retrospective, single-center, cross-sectional study. We included electively admitted DCM patients referred to our tertiary center for further diagnostic evaluation that underwent a clinically indicated right heart catheterization (RHC) and CMR within 24 h. PCWP invasively measured during RHC was used as the reference. LAEI was calculated from CMR-measured LA maximal and minimal volumes as LAEI = ( (LAVmax-LAVmin)/LAVmin) × 100. RESULTS: We enrolled 126 patients (47 ± 14 years; 68% male; PCWP = 17 ± 9.3 mmHg) randomly divided into derivation (n = 92) and validation (n = 34) cohorts with comparable characteristics. In the derivation cohort, the log-transformed (ln) LAEI showed a strong linear correlation with PCWP (r = 0.81, p < 0.001) and remained a strong independent PCWP determinant over clinical and conventional CMR parameters. Moreover, lnLAEI accurately identified PCWP ≥ 15 mmHg (AUC = 0.939, p < 0.001), and the optimal cut-off identified (lnLAEI ≤ 3.85) in the derivation cohort discriminated PCWP ≥ 15 mmHg with 82.4% sensitivity, 88.2% specificity, and 85.3% accuracy in the validation cohort. Finally, the equation PCWP = 52.33- (9.17xlnLAEI) obtained from the derivation cohort predicted PCWP (-0.1 ± 5.7 mmHg) in the validation cohort. CONCLUSIONS: In this cohort of DCM patients, CMR-measured LAEI resulted in a novel and useful parameter for non-invasive PCWP evaluation.

Validation of E/e' Using the Index-Beat Method as an Estimate of Left Atrial Pressure in Patients with Atrial Fibrillation.

INTRODUCTION: Echocardiographic assessment of diastolic function during atrial fibrillation (AF) remains challenging due to the irregular cardiac cycle length. We sought to assess whether the index-beat method, the beat following two preceding cardiac cycles of equal duration, could provide a more reliable measurement of E/e' (mitral E wave/diastolic tissue Doppler velocity) than the conventional averaging of consecutive beats and hence facilitate the noninvasive estimation of elevated left atrial pressure (LAP) in patients with AF. METHODS: We prospectively studied 35 patients with persistent AF who had preserved left ventricular ejection fraction and underwent radiofrequency ablation. LAP was measured in conjunction with transseptal puncture during catheter ablation. Echocardiography was performed 24 h before ablation and E/e' was determined using the recommended averaging of 10 beats and the index-beat method, with the observers blinded to the clinical details and LAP measurements. RESULTS: Correlation analysis showed a strong positive correlation between two methods in terms of both septal E/e' (r = 0.841, p < 0.001) and lateral E/e' (r = 0.930, p < 0.001). Bland-Altman analysis also showed a good agreement between the two measurement methods in terms of E/e'. E/e' determined using both conventional averaging and the index-beat method was significantly correlated with LAP (p < 0.05). After Fisher Z transformation, we found that the index-beat septal E/e' had a better correlation with LAP than did the conventional averaging E/e' (r = 0.736 vs. r = 0.392, Zr = -2.110, p = 0.035). Furthermore, the index-beat method took significantly less time to measure E/e' (mean 33.6 s; 95% confidence intervals [CIs]: 32.1 s-36.2 s) than did conventional averaging method (mean 96.2 s; 95% CI: 90.2 s-102.3 s; p < 0.001). Receiver operating characteristic curve analysis revealed that the optimal cut-off for predicting mean LAP >12 mm Hg was 11 (sensitivity 100%; specificity 77.3%) for index-beat septal E/e' and 16 (sensitivity 61.5%; specificity 95.5%) for index-beat lateral E/e'. CONCLUSIONS: Good correlations were found between E/e' and LAP in patients with AF, particularly with the index-beat method. Moreover, the index-beat method can easily measure E/e' at an accuracy similar to that for the conventional averaging of consecutive beats, which can therefore be applied to assess the diastolic dysfunction and potentially improve the diagnosis of heart failure in patients with AF.

E/e' Ratio Predicts the Atrial Pacing-Induced Left Atrial Pressure Response in Patients with Preserved Ejection Fraction.

Background and Objectives: Left atrial hypertension is one of the pathophysiologies of heart failure with preserved ejection fraction. We hypothesized that left atrial pressure response (LAPR) to incremental pacing is higher in patients with atrial fibrillation (AF) and can predict left ventricular diastolic dysfunction. Materials and Methods: Patients requiring left atrial access as a part of a therapeutic procedure for AF (n = 204, AF group) or supraventricular tachycardia (n = 34, control group) were analyzed (male n = 183, 54 ± 12 years old). LAPR was measured during incremental pacing. Results: Baseline left atrial pressure and LAPR at all pacing rates were not different between the AF and control groups. They were higher in patients with a high E/e' (≥ 8) than in those with a low E/e' (<8). LAPR at a pacing interval of 400 ms and E/e' were positively correlated (r = 0.373, p < 0.001). Body mass index and a high E/e' were independent predictors of pacing-induced left atrial hypertension. Conclusions: LAPR to incremental pacing was constant regardless of AF. The non-invasive echocardiographic marker E/e' reflected pacing-induced left atrial hypertension.

Increase in heart rate-dependent left atrial pressure is associated with symptoms in patients with paroxysmal atrial fibrillation.

BACKGROUND: It remains unclear why some patients with the same heart rate during an atrial fibrillation (AF) have subjective symptoms, whereas others do not. We assessed the hypothesis that different responses of arterial and left atrial blood pressures to rapid stimulation may be associated with the symptoms of AF. METHODS: A total of 110 patients who underwent catheter ablation for paroxysmal AF were retrospectively studied. Asymptomatic AF was defined as a European Heart Rhythm Association score of Ⅰ for AF-related symptoms. The left atrial pressure (LAP) was measured during sinus rhythm (SR), in 10 pacing per minute (ppm) increments from 100 ppm to the Wenckebach block rate in high right atrial pacing. RESULTS: Asymptomatic AF was observed in 19/110 patients (17%). Patients with symptomatic AF showed higher E/e' ratio and gradual LAP increase that was dependent on the pacing rate. Patients with asymptomatic AF had decreased LAP at 100 ppm compared that at SR, and thereafter, LAP gradually increased depending on the pacing rate. The rate of LAP change compared to that at SR was significantly lower in patients with asymptomatic AF than that in patients with symptomatic AF. The rate of LAP change was independently associated with AF symptoms. CONCLUSION: Patients with asymptomatic AF showed lower E/e' ratio and decreased LAP at 100 ppm to rapid stimulation, followed by a steady increase in LAP afterwards. Factors other than left ventricular diastolic dysfunction may be involved in AF symptoms.

Continuous atrial pressure monitoring via steerable guide catheter in transcatheter mitral and tricuspid edge-to-edge repair.

Transcatheter edge-to-edge repair (TEER) has emerged to address severe mitral and tricuspid valve regurgitation in patients who are at high perioperative risk for open-heart surgery. No clinical data is available for continuous left and right atrial pressure monitoring using the steerable guiding catheter (SGC) during TEER. In a prospective single-center study, 40 patients with severe mitral (n = 20) or tricuspid (n = 20) regurgitation underwent TEER with the registration of atrial pressure via the SGC. All patients had successful TEER using the PASCAL Ace repair system, while atrial pressure was monitored continuously via the SGC. Simultaneous right or left atrial pressure monitoring via the SGC and a pigtail catheter during mitral and tricuspid TEER showed excellent reliability for SGC pressure registration. While for mitral TEER the beneficial effects of continuous atrial pressure monitoring are well known, we further evaluated the outcome of patients with tricuspid TEER. Echocardiographic and clinical results after tricuspid TEER showed a reduction of quantitative echocardiographic tricuspid regurgitation parameters and improved New York Heart Association classification after 3-month follow-up. Also, qualitative tricuspid valve assessment showed improved tricuspid regurgitation classification postimplantation and at 3-month follow-up. Furthermore, right atrial pressure was reduced by 37.6% and mean right atrial pressure by 30.6% after successful tricuspid TEER using the PASCAL Ace device. Continuous atrial pressure monitoring using the SGC of the PASCAL Ace repair system is reliable during mitral and tricuspid TEER. Furthermore, successful tricuspid TEER leads to reduced right atrial pressure.

Bedside assessment of left atrial pressure in critical care: a multifaceted gem.

Evaluating left atrial pressure (LAP) solely from the left ventricular preload perspective is a restrained approach. Accurate assessment of LAP is particularly relevant when pulmonary congestion and/or right heart dysfunction are present since it is the pressure most closely related to pulmonary venous pressure and thus pulmonary haemodynamic load. Amalgamation of LAP measurement into assessment of the 'transpulmonary circuit' may have a particular role in differentiating cardiac failure phenotypes in critical care. Most of the literature in this area involves cardiology patients, and gaps of knowledge in application to the bedside of the critically ill patient remain significant. Explored in this review is an overview of left atrial physiology, invasive and non-invasive methods of LAP measurement and their potential clinical application.

The a' velocity by tissue-Doppler echocardiography correlates to invasive mean left atrial pressure in patients with normal ejection fraction.

OBJECTIVES: To evaluate the correlation of a' velocity by tissue-Doppler measurements with invasively measured mean left atrial pressure in patients with normal ejection fraction. DESIGN: In this retrospective study, we evaluated the septal a', lateral a' and average a' velocity by tissue-Doppler echocardiography, in 125 in-hospital patients, 1-12 h before an elective pulmonary vein isolation due to intermittent atrial fibrillation, and compared to invasively measured mean left atrial pressure (LAP) during the invasive procedure. The patients, aged 35-81 years, had to be in sinus rhythm at both examinations, no atrial fibrillation during two procedures, no or mild valve disease and normal ejection fraction (>50%). RESULTS: Invasively measured mean LAP correlated well to septal a' (r = -0.435), lateral a' (r = -0.473) and average a' velocity (r = -0.491). Normal mean LAP (≤12 mmHg) was found in 95 patients and elevated mean LAP (>12 mmHg) in 30 patients. The patients with elevated mean LAP had a lower septal a' velocity (6.5 ± 2.7 vs 8.6 ± 2.3 cm/s; p < .01), lateral a' velocity (5.9 ± 2.3 vs 8.6 ± 2.1 cm/s; p < .01) and average a' velocity (6.2 ± 2.4 vs 8.8 ± 2.1 cm/s; p < .01) compared to patients with normal mean LAP. Septal a', lateral a' and average a' velocity were good predictors of elevated mean LAP with AUC of 0.78, 0.83 and 0.82. Average a' velocity with cut-off < 7.25 cm/s had a sensitivity of 83% and a specificity of 77% to predict elevated mean LAP. CONCLUSION: The a' velocity is a good indicator of mean LAP and might be considered in the evaluation of left ventricle filling pressure in patients with normal ejection fraction.

Changes in left ventricular size, geometry, pump function and left heart pressures during healthy aging.

There are cross-sectional and longitudinal imaging studies using echocardiography and cardiac magnetic resonance in healthy adult subjects which have demonstrated associations of left ventricular (LV) structure and pump function with age. There are also cross-sectional data regarding the relationships of age with invasively measured left heart chamber pressures. Increasing age is associated with decreases in LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), end-diastolic length (LVEDL), stroke volume (SV) and cardiac output (CO), and increases in relative wall thickness (RWT), LV mass/LVEDV ratio (LVMVR) and ejection fraction (LVEF). Older age is not accompanied by a change in mean left atrial (LA) pressure, but there is both direct and indirect evidence which suggests that LV end-diastolic pressure (LVEDP) increases with age. LVEDV remains lower in older than younger subjects during fluid infusion and the resulting increases in LA pressure. The combination of an increase in LVEF with reductions of both SV and CO demonstrates an age-related increase in divergence between LVEF and LV pump function. A lower LVEDV in older compared to younger subjects can be characterized as an aging-related decrease in LV capacity, with the higher LVEDP in older subjects also indicating a reduction of preload reserve.

Clinical Effect of Adaptive Servo-Ventilation on Left Atrial Pressure During Catheter Ablation in Sedated Patients With Atrial Fibrillation.

BACKGROUND: Sedation during pulmonary vein isolation (PVI) for atrial fibrillation often provokes a decline in left atrial (LA) pressure (LAP) under atmospheric pressure and increases the risk of systemic air embolisms. This study aimed to investigate the efficacy of adaptive servo-ventilation (ASV) on the LAP in sedated patients.Methods and Results:Fifty-one consecutive patients undergoing cryoballoon PVI were enrolled. All patients underwent sedation using propofol throughout the procedure. After the transseptal puncture and the insertion of a long sheath into the LA, the LAP was measured. Then, the ASV treatment was started, and the LAP was re-measured. The LAP before and after the ASV support was investigated. Before ASV, the LAP during the inspiratory phase was significantly smaller than that during the expiratory phase (4.9±5.4 mmHg vs. 14.0±5.2 mmHg, P<0.01). The lowest LAP was -2.2±5.1 mmHg and was under 0 mmHg in 37 (73%) patients. After the ASV, the LAP during the inspiratory phase significantly increased to 8.9±4.1 mmHg (P<0.01), and lowest LAP increased to 4.7±5.9 mmHg (P<0.01). The negative lowest LAP value became positive in 30/37 (81%) patients. There were no statistical differences regarding obstructive sleep apnea (OSA), obesity, gender, or other comorbidities between patients with and without a negative lowest LAP after ASV support. CONCLUSIONS: ASV is effective for increasing the LAP above 0 mmHg and might prevent air embolisms during PVI.

Utility of transesophageal echocardiography to assess real time left atrial pressure changes and dynamic mitral regurgitation following placement of transseptal multistage venous cannula for systemic venous drainage and indirect left ventricular venting in venoarterial extracorporeal membrane oxygenation.

A patient with heart failure due to nonischemic cardiomyopathy presented as a transfer to our institution following peripheral (femoral) venoarterial (VA) extracorporeal membrane oxygenation (ECMO) placement. With peripheral VA ECMO cannulation, the patient continued to have unstable ventricular tachyarrhythmias. Echocardiography demonstrated left ventricular (LV) dilation and severe mitral regurgitation (MR) with clinical and chest X-ray evidence of pulmonary edema. To provide venous drainage and simultaneous decompression of the left atrium (LA) and thereby indirect LV venting, a single multistage venous cannula was placed across the inter-atrial septum (IAS) using the previously described left atrial venoarterial (LA-VA) ECMO cannulation technique. Two- and three-dimensional (3D) transesophageal echocardiography (TEE) demonstrated utility in guiding cannula placement into the appropriate position and providing real time assessment of ventricular decompression and MR severity. There was subsequent improvement in pulmonary edema. This case is thought to be the first demonstration of real time resolution of pulmonary venous flow reversal in a patient undergoing LA-VA ECMO cannulation. This demonstration offers important mechanistic insight into some of the potential benefits of such an approach.

Left Atrial Strain as a Single Parameter to Predict Left Ventricular Diastolic Dysfunction and Elevated Left Ventricular Filling Pressure in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting.

OBJECTIVE: Left ventricular diastolic dysfunction (LVDD) is very common among patients undergoing cardiac surgery and is associated with increased mortality and morbidity. The present study tested the hypothesis of whether left atrial strain (LAS) can be used as a single parameter to predict LVDD (per 2016 LVDD evaluation guidelines) and elevated left ventricular filling pressure (LVFP) (ie, LVDD grades II and III) in patients scheduled for off-pump coronary artery bypass grafting (OPCABG) surgery. DESIGN: A prospective observational study. SETTINGS: Tertiary-care level hospital. PARTICIPANTS: The study comprised 60 patients undergoing elective OPCABG. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Transthoracic echocardiography was performed within 24 hours of surgery by an anesthesiologist. LVDD was graded per American Society of Echocardiography/European Association of Cardiovascular Imaging recommendations for 2016 LVDD guidelines. Left atrial (LA) function was evaluated using two-dimensional strain measurements obtained with the speckle-tracking echocardiography technique. Receiver operating characteristic curves were constructed, and the area under the curve was derived for the prediction of elevated LVFP by LAS. Fourteen (23.3%) patients had elevated LVFP. Global LA reservoir strain (LASr) reduced significantly as the LVDD grade worsened (28.9% ± 8.3%, 21.8% ± 7.2%, 15.6% ± 4.5% and 11.9% ± 1.3%, respectively, for normal LV diastolic function and grades I, II, and III LVDD; p < 0.0001). Similar trends were noted for other components of LAS; namely, global LA conduction, global LA contraction strain, and LAS rate. The ability to predict high LVFP with LASr was statistically significant, with an area under the receiver operating characteristic curve of 0.92 (confidence interval 0.82-0.97; p < 0.001), and a Youden's index for LASr of 19% was obtained with 85.71% sensitivity and 84.78% specificity. The ability of LAS and its components to predict increased LVFP in various subpopulations (normal v reduced ejection fraction) yielded statistically significant results. CONCLUSIONS: In patients scheduled for OPCABG, cardiac anesthesiologists successfully could measure LAS with speckle-tracking echocardiography in the preoperative period. LAS as a single parameter was significantly associated with the grade of LVDD. LASr decreased significantly with worsening grade of LVDD. Furthermore, an LASr value <19% significantly predicted a high LVFP, and LASr predicted high LVFP in both preserved and reduced ejection fraction equally well.

Silence Is Golden.

Speech-induced atrial tachycardia (AT) is extremely rare. We presented a case of focal AT that could be triggered by speech and terminated with the cessation of conversation. An electrophysiological study showed that the outbreak was associated with left atrial pressure rose. Radiofrequency ablation at the left atrial posterior-superior wall (earliest activation site) resulted in the immediate termination of AT. These electrophysiological characteristics indicated that the cardiac autonomic nervous system and/or left atrial pressure might play essential roles in the occurrences of speech-induced AT.

The hemodynamic effect of different left ventricular unloading techniques during veno-arterial extracorporeal life support: a systematic review and meta-analysis.

BACKGROUND: Pulmonary edema and left ventricular thrombosis may arise during veno-arterial extracorporeal life support due to an increase in cardiac load. This mechanical stress can be reduced through different left ventricular unloading techniques. We set out to quantitatively summarize the hemodynamic effects of available methods in patients treated with veno-arterial extracorporeal life support. METHODS: Literature was systematically searched for studies reporting left ventricular unloading during veno-arterial extracorporeal life support as reflected by changes in left atrial pressure, pulmonary capillary wedge pressure, diastolic pulmonary artery pressure, or left ventricular end-diastolic pressure. For studies including ⩾10 patients per group, changes in these parameters were pooled using (1) standardized mean differences and (2) ratio of means. Assessment of potential bias was performed for all studies. RESULTS: Eight studies met the inclusion criteria. Reported techniques included use of intra-aortic balloon pump (n = 1), micro-axial blood pump (Impella®, n = 2), left ventricular venting (n = 1), and atrial septostomy (n = 4). Overall, left ventricular unloading was associated with a statistically significant reduction in preload parameters (standardized mean differences = -1.05 (95% confidence interval = -1.24 to -0.86) and ratio of means = 0.60 (0.47 to 0.76)). Effect sizes were strongest for micro-axial blood pump and atrial septostomy (standardized mean differences = -1.11 (-1.55 to -0.68) and -1.22 (-1.47 to -0.96), and ratio of means = 0.58 (0.39 to 0.86) and 0.54 (0.36 to 0.83), respectively). CONCLUSION: Left ventricular unloading was associated with a significant reduction in left ventricular preload parameters in the setting of veno-arterial extracorporeal life support. This effect may be most pronounced for micro-axial blood pump and atrial septostomy.

Intraprocedural direct left atrial and wedge pressure correlation during transcatheter mitral valve repair: Results from a single center registry.

OBJECTIVES: This study investigates the correlation of occlusive wedge pressure (WP) with direct left atrial (LA) pressure in patients with severe mitral regurgitation (MR) undergoing transcatheter mitral valve repair (TMVr) with MitraClip. BACKGROUND: There is interest in acquiring objective hemodynamic parameters for intraprocedural guidance in patients undergoing MitraClip. METHODS: The study included 94 patients with severe MR at prohibitive surgical risk who underwent MitraClip at the University of California Davis Medical Center between 2014 and 2016. RESULTS: An average of 1.8 ± 0.7 clips were used to achieve MR grade of 2+ or less in 99% of patients. Correlation analysis of all (n = 236) pre-clip, inter-clip, and final-clip WP and LA pressures yielded a Pearson's R (r) of 0.85 and 0.79 for mean WP vs mean LA and WP V vs LA V, respectively. Median LA V to mean LA ratio (LAV:mLA) was 1.75 (IQR 1.5-1.9). 79% (n = 74) of patients had LAV:mLA ratio ≥ 1.5 with associated WP V vs LA V correlation (r) of 0.83. In patients with LAV:mLA ratio < 1.5, the correlation (r) was 0.69. Baseline characteristics were not significantly different between patients with LAV:mLA ratio ≥ 1.5 and patients with LAV:mLA ratio < 1.5. Post-procedure, median LA V: mean LA ratio decreased from 1.75 to 1.4, P = 0.0001. CONCLUSIONS: Correlation between WP and direct LA pressure in patients with severe MR undergoing Mitraclip is modest. Caution is advised when using WP to approximate LA pressure intraprocedurally, especially in patients with baseline low LAV:mLA ratios.

A simple technique for bedside estimation of left atrial pressure.

BACKGROUND: Distinguishing cardiac from noncardiac causes of dyspnea is clinically important, and a reliable noninvasive measure of left atrial pressure (LAP) is needed. Subtracting the peak systolic gradient between left ventricle (LV) and left atrium (LA) from the central systolic blood pressure (BP) should provide this measure. Using a commercially available blood pressure system incorporating applanation tonometry and bedside echocardiography, we tested this hypothesis in a broad spectrum of patients. METHODS: A total of 75 stable patients, scheduled for right heart catheterization for any reason, were included. Central systolic pressure was measured by a Sphygmocor® tonometry system; peak LV-LA gradient was calculated as 4*(peak mitral regurgitation (MR) velocity)2 . Microbubble contrast was used as needed to augment the MR signal. LAP estimates using central BP were compared with wedge pressure as were LAP estimates using brachial BP. RESULTS: Left atrial pressure estimates using central BP showed a good correlation with wedge pressure (r2  = 0.774, P < .0001) while estimates using brachial systolic BP did not (r2  = 0.157, P = .0006). Using central BP, correlations between LAP and wedge were similar among groups with varying degrees of MR and normal vs reduced ejection fraction. CONCLUSIONS: The use of central systolic BP and peak LV-LA gradient by bedside echocardiography holds promise as a noninvasive measure of LAP. Our results are similar to those provided using current guidelines for echocardiographic estimation of LAP. Increased precision in the measurement of LV-LA gradient would improve the accuracy of this new technique.

Diastolic dysfunction is associated with exercise impairment in patients with sickle cell anemia.

BACKGROUND: Left ventricular diastolic dysfunction (DD) is an independent risk factor for mortality in sickle cell anemia (SCA) and is associated with increased extracellular volume (ECV) on cardiac MRI (CMR). Exercise impairment is common in SCA, but its causes and prognostic value are not well understood. OBJECTIVE: To study the effects of DD and ECV on cardiopulmonary exercise test (CPET) in patients with SCA. METHODS AND RESULTS: As part of a prospective study to characterize the cardiomyopathy of SCA (NCT02410811), 20 children and adults with SCA underwent CMR, echocardiography, and cycle ergometer CPET (age range 8-43 years). Maximum exercise was reached in 18 patients and 17 (94%) had reduced exercise capacity (%predicted VO2 less than 80%). Six patients had DD and none had systolic dysfunction. Patients with DD had lower exercise capacity compared to patients with normal diastolic function (%predicted VO2 48.2 ± 9.1% vs. 61.2 ± 11.7%; P = 0.01). The z-score of left ventricular lateral E/e' ratio, which is a marker of DD, was negatively associated with %predicted VO2 (r = -0.61, P = 0.01). All patients with moderate-to-severe exercise impairment (%predicted VO2  < 60%) had lateral E/e' z-score > 2. In a multivariate analysis, lateral E/e' z-score was independently associated with %predicted VO2 (P = 0.02). All participants had elevated ECV but the degree of elevation was not associated with exercise parameters. CONCLUSION: Left ventricular DD is associated with decreased exercise capacity in SCA. Interventions to prevent or delay DD could improve exercise capacity, quality of life, and long-term outcomes in SCA.