Stiff Left Atrial Syndrome Research Articles

Changes in pulmonary arterial pressure after atrial fibrillation ablation: incidence, causes, and implications on the stiff left atrial syndrome

Purpose: The left atrial (LA) syndrome is defined as pulmonary hypertension (PH) secondary to reduced LA compliance. While decreased LA compliance is one possible cause of PH after atrial fibrillation (AF) ablation, our study examines the incidence of an increase in pulmonary arterial (PA) pressure post-ablation and the potential underlying mechanisms. Methods: Patients who underwent AF ablation between 1999 and 2011 were included if they had both an echocardiogram within 6 months prior to the procedure and between 1 week and 6 months after the procedure. Patients were then separated into two groups with the increased PA pressure group defined as patients with > 10 mmHg increase in right ventricular systolic pressure (RVSP) post-ablation and a post-ablation RVSP > 35 mmHg. Categorical parameters were compared using a Chi-square test for independence. Continuous parameters were compared with a Wilcoxon rank-sum test. Results: Of the 499 patients meeting study criteria, 41 (8.2%) had an increase in RVSP > 10 mmHg and RVSP > 35 mmHg post-ablation. The group which developed an increase in PA pressure had an older age, higher BMI, larger LA volume, and greater prevalence of coronary artery disease and valvular disease. On echo, the two groups had similar E/A and E/e' ratios pre-ablation. However, post-ablation the increased PA pressure group had higher E/A (2.12 versus 1.49, P=0.002) and E/e' ratios (14.7 vs. 11.2, P=0.006). LA expansion index values were lower in the increased PA pressure group pre-ablation (51% vs. 92%, P<0.0001), but not significantly different post-ablation (82% vs. 88%, P=0.44). Conclusions: Around 8% of patients develop an increase in estimated PA pressure after AF ablation. However, a stiff left atrium does not appear to be the most common mechanism, as evidenced by LA expansion index values. Echocardiographic parameters suggest that patients who develop increased PA pressure are developing (or unmasking) left ventricular diastolic dysfunction. These data do not rule out the LA syndrome as a cause of an increase in PA pressure in some patients, but suggest that LV diastolic dysfunction is a prominent cause of an increase in PA pressure after AF ablation.

Standard and Novel Echocardiographic Parameters Improve Risk Assessment of the Seattle Heart Failure Model in Patients Referred for LVAD and/or Transplantation

Hg. Mean left atrial volume index was 49.8617.1 sq cm. After the initial diagnosis with a two year followup, there were no readmissions in 65.3% of patients who were on appropriate diuretic therapy and had regular clinical visits. Frequent readmissions were seen in 34.7% of patients inspite of appropriate diuretic therapy. All-cause mortality rate was 4.3% at two year follow up. Conclusions: In patients with stiff left atrial syndrome, most consistent associated features were increased mean pulmonary capillary wedge pressure with significantly peaked V waves on right heart catheterization and increased left atrial size. Based on established diagnosis, judiciously directed therapeutic strategies with diuretics were shown to prevent hospital readmissions and improve long term clinical outcomes. Inspite of awareness of this unique clinical entity, it is still poorly understood and appropriate therapeutic regimens to stabilize or stem disease progression are still elusive.

Recurrent dyspnea following multiple ablations for atrial fibrillation explained by the “stiff left atrial syndrome”

We present the case of a patient who underwent repeated ablations for atrial fibrillation and presented with recurrent dyspnea, elevated left atrial pressure with large V waves in the absence of mitral regurgitation. This case provides an example of "stiff left atrial syndrome" as has been described in patients with mitral valve replacement and only recently in patients with radiofrequency ablations for atrial fibrillation.

Pulmonary Hypertension Following Maze Surgery for Atrial Fibrillation

Purpose The Maze procedure is considered the definitive surgical approach to atrial fibrillation. Pulmonary hypertension (PH) has not been reported following Maze, but has been associated with radiofrequency ablation due to left atrial scarring and diastolic dysfunction (stiff left atrial syndrome). We sought to investigate the development of PH following Maze using echocardiographic indices. Methods and Materials Data from all patients undergoing Maze surgery between 1/1/1999 and 12/31/2004 at Mayo Clinic Rochester was retrospectively reviewed. Patients with adequate pre- and post-operative transthoracic echocardiograms (TTE) (>90 days after surgery) were included. Patients with congenital heart disease, isolated right-sided Maze, mitral stenosis, and pre-existing elevated right ventricular systolic pressure (RVSP ≥40 mm Hg) were excluded. Diastolic parameters including left atrial volume index, E/e’, and E:A were reported when available. Results Forty-one patients (26 males) met inclusion criteria. Mean age at surgery was 63 ± 10 years, with normal ejection fraction pre- and post-operatively (60 vs 58%). Two patients underwent Maze surgery only, 5 had coronary bypass grafting, 36 had concomitant valvular operations (29 mitral, 4 aortic, 3 tricuspid), and 2 underwent septal myectomy for hypertrophic obstructive cardiomyopathy. Median RVSP increased from 32 mm Hg (interquartile range [IQ] 27;37) pre-operatively to 41 mm Hg (IQ 33;58) post-operatively. RVSP ≥40 mm Hg was observed in 26/41 patients on 150 total post-operative TTEs at a median follow-up of 1545 days (IQ 610;2339). Measures of left ventricular diastolic function worsened, with median pre-operative E/e’ of 14 (IQ 10;18) increasing to 22 (IQ 15;28), and median E:A ratio increasing from 1.8 (IQ 1.1;2.4) to 2.33 (IQ 2.0;3.3). Conclusions Maze surgery may be complicated by the development of increased right heart pressures and worsening diastolic function, raising the possibility that stiff left atrial syndrome may be a significant sequela of Maze surgery warranting further study.

Hemodynamic Changes after Surgical MAZE: Pulmonary Hypertension Secondary to Stiff Left Atrial Syndrome?

Purpose Surgical MAZE procedure remains an effective treatment for atrial fibrillation but may result in hemodynamic changes with development of pulmonary hypertension (PH) secondary to left-sided heart disease, previously unreported in the literature. Methods and Materials A review of all patients undergoing MAZE procedure between 1/1/1999 and 12/31/2004 was performed. All patients had pre- and post-operative 2D echocardiograms (>3 months after MAZE). Estimated right ventricular systolic pressure (RVSP) cutoff ≥40 mm Hg on echocardiogram was suggestive of elevated right-sided pressures. Exclusion criteria included congenital heart disease, pre-operative RVSP >40 mm Hg, pre-op pulmonary hypertension, and mitral stenosis. Right heart catheterization was performed on patients with unexplained dyspnea in post-operative setting. Results Forty-one patients (26 males) with an average age of 63±10 years met inclusion criteria. The majority of patients (26/41, 63%) had post-op RVSP ≥40 mm Hg. Median pre-op RVSP was 32 mm Hg (IQ 27;37) with an increase in post-op RVSP to 41 mm Hg (IQ 33;58). Increase in RVSP was significant at 5 years (13±16 mm Hg; p=0.0005) post-Maze corresponding with an increase in RV size at 5 years and worsening RV systolic function. Eight patients underwent right heart catheterization. Mean RVSP was 53±13 mm Hg with a right atrial pressure of 14 ± mm Hg. Mean pulmonary artery pressure was 35±7 mm Hg with mean pulmonary capillary wedge pressure of 19±5 mm Hg and mean v wave of 27±6 mm Hg. Mean transpulmonary gradient was 16±6 mm Hg. Development of PH adversely impacted 10-year survival (p=0.03). Conclusions Surgical MAZE can by complicated by PH seen both noninvasively and invasively. The hemodynamic pathophysiology is mediated by left atrial noncompliance or Stiff Left Atrial Syndrome and may be a significant complication following surgical MAZE procedure, warranting further investigation.

Stiff left atrial syndrome after catheter ablation for atrial fibrillation: Clinical characterization, prevalence, and predictors

There have been no studies of atrial diastolic function after catheter ablation of atrial fibrillation (AF). We encountered a few patients with symptomatic left atrial (LA) diastolic dysfunction and associated pulmonary hypertension (PH) that developed after catheter ablation for atrial fibrillation. Similar findings were described in patients after cardiac surgery and were referred to as the "stiff left atrial syndrome." The purpose of this study was to prospectively quantify the incidence of patients developing PH associated with diastolic hemodynamic abnormalities of the LA after radiofrequency ablation of AF and to identify the possible predictors. Between January 2009 and July 2010, data on 1,380 consecutive patients were prospectively collected. Before ablation and at follow-up, all patients had an echocardiogram to assess for the presence of PH. Patients with no echocardiographic evidence of PH but complaining of unexplained dyspnea with LA diastolic abnormalities were evaluated with right heart catheterization (RHC). Patients were included in the analysis if they developed new or worsening PH postablation with evidence of LA diastolic dysfunction by RHC or direct LA pressure measurement. All patients were evaluated for pulmonary vein stenosis and excluded if this condition was identified. The mean age was 62 ± 11 (75% male), and nonparoxysmal AF was the predominant arrhythmia (71%). New or worsening PH with associated LA diastolic abnormalities was detected in 19 (1.4%) patients after ablation. The prevalence of PH did not differ between AF types (P = .612). Compared with patients who did not develop PH, LA scarring (P <.001), diabetes (P = .026), and obstructive sleep apnea (OSA; P = .006) were more frequently observed among those who developed PH. In a multivariable logistic model, preprocedure LA size ≤45 mm (odds ratio [OR] = 6.13; P = .033), mean LA pressure (OR 1.14; P = .025), severe LA scarring (OR = 4.4; P = .046), diabetes mellitus (OR = 9.5; P = .004), and OSA (OR = 6.2; P = .009) were independently associated with the development of PH postablation. After radiofrequency catheter ablation of atrial fibrillation (RFCAF), PH with LA diastolic dysfunction or the so-called stiff LA syndrome is a rare but potentially significant complication of AF ablation. Severe LA scarring, LA ≤45 mm, diabetes mellitus, OSA, and high LA pressure are clinical variables that predict the development of this syndrome. The main clinical findings include dyspnea, congestive heart failure, PH, and large V waves on pulmonary capillary wedge pressure (PCWP) or LA pressure tracings in the absence of mitral regurgitation.