TAVI for low-flow, low-gradient severe aortic stenosis: impact on outcome

Background

Several factors have been identified as predictors of events after transcatheter aortic valve implantation (TAVI) but the impact of transaortic flow (F) and mean transaortic gradient (MG) upon outcomes is controversial. This study aimed to clarify the prognostic role of low FL and low MG after TAVI.

Methods

Patients with severe and symptomatic aortic stenosis [effective orifice area (EOA) ≤1cm2], referred for TAVR at our institution were consecutively enrolled. Given the aim of this analysis, patients were divided according to F and MG into four groups: 1) LF-LG Patients with low flow (SVi <35ml/m2) and low mean gradient (MG <40mmHg), 2) NF-LG Patients with normal flow (SVi ≥35ml/m2) and low mean gradient (MG <40mmHg), 3) LF-HG Patients with low flow (SVi <35ml/m2) and high mean gradient (MG ≥40mmHg) and 4) NF-HG patients with normal flow (SVi ≥35ml/m2) and high mean gradient (MG ≥40mmHg). Prospectively collected demographic, laboratory and echocardiographic data were retrospectively analyzed. One-year outcomes were compared between the 4 groups of patients. Primary clinical endpoint was all-cause mortality at long term follow up, as defined by the criteria proposed by the Valve Academic Research Consortium2.

Results

In total 255 patients undergoing TAVI at our institution were included in our study: 35 (13.7%) patients with LF-LG, 17 (6.7%) with NF-LG, 108 (42.4%) with LF-HG and 95 (37.3%) with NF-HG. There was a statistically significant difference in gender distribution between the groups with most females being represented in the NF-HG group (64.2%) vs the LF-LG (31.4%), the NF-LG (47.1%) or the LF-HG group (50.9%) (p=0.008). Moreover, LF-LG patients were younger than NF-LG, LF-HG or NF-HG patients (ANOVA, p=0.037). There was a greater prevalence of prior myocardial infarction (MI) in the LF-LG group (34.5%) vs 20% in the NF-LG, 16.1% in the LF-HG and 20.2% in the NF-HG group (p=0.005). At 1 year follow up there were no statistically significant differences in major vascular complication, major bleeding complication or permanent pacemaker implantation rates between the groups, (all p>0.05). At a median follow up of 36 months IQR (17, 56) all-cause mortality was significantly higher in the LF-LG group as opposed to the NF-LG, LF-HG and NF-HG groups (77.41% vs 60% vs 55.67% vs 46.15% respectively, p=0.005). These results were confirmed by multivariate logistic regression analysis, as the combination of low flow and low mean gradient emerged as the strongest long term all cause mortality predictor (HR: 5.39, 95% confidence intervals: 1.72–16.83; p=0.004)

Conclusion

Combination of low flow and low mean transaortic gradient portends a worse prognosis after TAVI.

Funding Acknowledgement

Type of funding sources: None.

Impact of significant preprocedural mitral regurgitation on mortality after transcatheter aortic valve implantation

Background

Mitral regurgitation (MR) is commonly encountered in patients with severe aortic stenosis scheduled for transcatheter aortic valve implantation (TAVI). The presence of significant pre-procedural MR, however, has not been accounted in pivotal trials of TAVI and data regarding its independent impact on outcome are contradictory.

Methods

Patients with severe and symptomatic aortic stenosis [effective orifice area (EOA) ≤1cm2] referred for TAVI at our institution were consecutively enrolled. Prospectively collected demographic, laboratory and echocardiographic data were retrospectively analysed. Patients were stratified into two groups according to MR severity: ≤ grade 1 were defined as non-significant and ≥ grade 2 as significant. Change in MR was determined by comparison between baseline and 30-day echocardiogram. Primary clinical endpoint was all-cause mortality, as defined by the criteria proposed by the Valve Academic Research Consortium2.

Results

A total of 331 consecutive patients were enrolled in the study: 247 (74.6%) had non-significant MR and 84 (25.4%) patients had significant MR at baseline. Patients with significant pre-procedural MR had lower baseline ejection fraction (47.7±10.4% versus 51.2±8.4%, p=0.002), higher pulmonary artery systolic pressure (52±14.3mmHg versus 42.5±11.1mmHg, p<0.0001) and higher rates of moderate or severe tricuspid regurgitation (TR) (50% versus 19.4%) compared to patients with non-significant MR. Of all patients, mitral regurgitation improved in 9.5%, remained the same in 83.9%, and worsened in 6.6% 30 days after TAVR. In a multivariable analysis, pre-procedural TR severity was predictor of improved mitral regurgitation [OR 3.003,(95% CI 1.216–7.417, p=0.017)].

The primary clinical end point occurred in 44.7% of all patients during a follow-up period of 36.6.±25.9 months. Patients with significant pre-procedural MR had significantly higher rates of all-cause mortality compared to patients with non-significant (54.7% and 41.3%, respectively; log rank p=0.015). Performing a multivariable analysis demonstrated that preprocedural MR severity could independently predict cumulative mortality [OR 0.480, (95% CI 0.247–0.932, p=0.03)].

Conclusion

Significant pre-procedural MR is common in patients undergoing TAVI and is associated with increased all-cause mortality. TAVI is associated with a significant improvement in MR, especially in severe types. These data provide new insights in the crucial role of mitral regurgitation in the risk assessment of TAVI candidates.

Funding Acknowledgement

Type of funding sources: None.

Effect of concomitant atrioventricular valve regurgitation on the outcome after transcatheter aortic-valve implantation

Background

Many patients undergoing transcatheter aortic valve implantation (TAVI) have concomitant mitral regurgitation (MR) of moderate grade or more. The impact of coexistent tricuspid regurgitation (TR) remains to be determined.

Methods

Patients with severe and symptomatic aortic stenosis [effective orifice area (EOA)≤1cm2] referred for TAVI at our institution were consecutively enrolled. Prospectively collected demographic, laboratory and echocardiographic data were retrospectively analysed. Patients were divided into 4 groups according to MR and TR severity pre-procedurally: no/mild MR and TR, moderate/severe MR, moderate/severe TR, moderate/severe MR and TR. Primary clinical endpoint was all-cause mortality, as defined by the criteria proposed by the Valve Academic Research Consortium2.

Results

A total of 244 consecutive patients were enrolled in the study: 148 (60.7%) patients no/mild MR and TR, 32 (13.1%) moderate/severe MR, 35 (14.3%) moderate/severe TR, 29 (11.9%) moderate/severe MR and TR pre-procedurally. There was significant difference in pre-procedural pulmonary artery systolic pressure (PASP) among groups (no/mild MR and TR: 40.8±10 mmHg, moderate/severe MR: 46.6±11.2 mmHg, moderate/severe TR: 49.9±13mmHg, moderate/severe MR and TR: 59.8±15.2mmHg, p<0.0001). The Kaplan–Meier curves for 2 year mortality showed that the severity of TR was associated with poor survival. Interestingly, patients with moderate/severe MR and TR had the worse survival (no/mild MR and TR (91.2%), moderate/severe MR (78.1%), moderate/severe TR (62.9%), moderate/severe MR and TR (62.1%), p<0.0001).

Conclusion

The presence of concomitant moderate or severe mitral and tricuspid valve regurgitation was associated with the higher mortality. This suggests that a thorough evaluation of the mechanisms underlying concomitant mitral and tricuspid valve regurgitation should be performed to determine the best strategy for avoiding TAVI-related futility.

Funding Acknowledgement

Type of funding sources: None.

Novel computed-tomography derived prognostic markers in patients undergoing TAVI with a self-expanding valve

Introduction

Transcatheter aortic valve implantation is the treatment of choice in a consistently expanding group of patients with severe aortic valve stenosis. Tricuspid and mitral annular dilatation with consequent valvular regurgitation are associated with adverse outcome. Computed tomography angiography (CTA) is routinely performed for preprocedural evaluation of vascular access and prosthesis sizing.

Purpose

To evaluate the impact of mitral and tricuspid annular dimensions in preprocedural CTA on prognosis of patients undergoing TAVI with a self-expanding valve.

Methods

CTAs of consecutive patients undergoing TAVI in a single high-volume center between 2016 and 2019 were retrospectively evaluated. Maximal septolateral tricuspid annular diameters (TAD) and mitral annular diameters (MAD) were obtained and measured from properly angulated three dimensional CTA datasets. Moreover, maximal pulmonary artery diameter perpendicular to the long axis was measured in every patient. Patients were followed up by clinical visits or telephone contacts. As clinical events were defined all-cause mortality, stroke and heart failure hospitalization.

Results

In total 123 patients were included in the study. The mean follow-up duration was 875±383 days and 21 clinical events were recorded. There was a moderate but statistical significant correlation between TAD and both pulmonary artery diameter (r=0.39, p<0.001) and pulmonary artery systolic pressure by echocardiography (r=0.23, p=0.015). In univariate logistic regression analysis pulmonary artery diameter and TAD were both associated with heart failure hospitalization (p=0.03 and 0.02 respectively). In addition, MAD was associated with total events (OR: 0.43, 95% CI 0.19–0.99, p=0.048). The relationship of MAD with events remained significant after adjustment for sex, age and tricuspid annular dimensions (OR: 0.28, 95% CI 0.1–0.79, p=0.02).

Conclusions

TAD and MAD were associated with heart failure rehospitalization and clinical events respectively in patients undergoing TAVI with a self-expanding valve. Further larger prospective studies are warranted to evaluate the prognostic value of these CTA markers.

Funding Acknowledgement

Type of funding sources: None.

Percutaneous access versus surgical cutdown in TAVI: vascular and bleeding complications

Background

Access options for transcatheter aortic valve implantation (TAVI) are vital, since use of large sheaths may lead to access-related complications and bleeding.

Purpose

To determine the access-related vascular and bleeding complications of patients undergoing transfemoral TAVI.

Methods

Consecutive patients scheduled for transfemoral TAVI were retrospectively grouped according to vascular access [percutaneous access (p-TAVI) and surgical cutdown (sc-TAVI)]. Primary end points were vascular and bleeding complications, based on the VARC-II criteria.

Results

Totally, 187 patients were included in the analysis (p-TAVI: 124 patients; sc-TAVI: 63 patients). Mean procedure time was shorter in the p-TAVI group compared to the sc-TAVI group (45.65±6.17 min versus 64.05±15.73 min, p<0.001). Contrast use was lower in the p-TAVI group compared to the sc-TAVI group (81.18±15.96 ml versus 106.75±25.67 ml, p<0.001), which resulted in higher rates of acute kidney injury in the sc-TAVI group (13% versus 1%, p=0.01). Vascular access complications occurred numerically but not statistically more often in the p-TAVI group compared to the sc-TAVI group (11% versus 5% for minor complications and 6% versus 3% for major complications respectively, p=0.10). Patients in the p-TAVI group had the same minor and major bleeding complications compared to the sc-TAVI group (11% versus 8% for minor, 10% versus 6% for major bleeding complications respectively, p=0.49), but no life-threatening bleeding (0% versus 1.5%).

Conclusions

Transfemoral access options in TAVI (surgical cutdown or percutaneous) have similar efficacy and should be offered in TAVI patients if and when appropriate.

Funding Acknowledgement

Type of funding sources: None.

One-year echocardiographic outcomes of transcatheter aortic valve implantation with or without predilatation of the aortic valve: insights from the multicenter, randomized DIRECT trial

Introduction

Transcatheter aortic valve implantation (TAVI) has become the standard of care for high-risk and inoperable surgical patients and a valid alternative in intermediate-risk patients with severe aortic stenosis.The DIRECT trial (Predilatation in Transcatheter Aortic Valve Implantation Trial) was a multicenter, randomized, clinical trial designed to evaluate the safety and efficacy of TAVI with or without balloon aortic valvuloplasty (BAV) in patients with symptomatic, severe aortic valve stenosis.

Purpose

To compare the one year echocardiographic findings among patients, who underwent TAVI using a self-expanding valve with or without BAV.

Methods

A total of 171 patients with severe aortic stenosis were randomly assigned at 4 tertiary centers to undergo TAVI with the use of self-expanding prostheses with (pre-BAV) or without pre-dilatation (no-BAV). Follow up transthoracic echocardiography was performed 1 year after TAVI.

Results

Of 171 patients, 86 patients were randomized to pre-BAV group and 85 to no-BAV group. One year echocardiographic follow up was available in 146 patients. In one year follow up there was no significant difference between pre-BAV and no-BAV group in aortic valve area (1.84±0.39cm2 vs. 1.85±0.44cm2, p=0.79), peak aortic valve gradient (15.95±9.97 mmHg vs. 14.51±6.60 mmHg, p=0.35), mean aortic valve gradient (8.37±5.01 mmHg vs. 7.99±4.04 mmHg, p=0.64), aortic valve peak velocity (1.90±0.51 m/s vs. 1.80±0.42m/s, p=0.24), ejection fraction (54.19±8.36% vs. 53.19±9.58%, p=0.52) and pulmonary artery systolic pressure (41.86±14.34 mmHg vs. 40.71±12.40 mmHg, p=0.64). The incidence of moderate or severe paravalvular regurgitation (PVL) in 1 year follow up was 6.2% without significant difference between the 2 study groups (5.7% in the no-BAV group vs. 6.6% in the pre-BAV group, p=0.83).

Conclusions

Direct transcatheter aortic valve implantation has no impact on one-year prosthesis function and PVL in patients undergoing TAVI with self-expanding valve

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Medtronic

Echocardiographic assessment of functional changes of prosthetic valve after transcatheter aortic valve implantation in one year follow up: insights from the multicenter, randomized DIRECT trial

Introduction

The DIRECT trial (Predilatation in Transcatheter Aortic Valve Implantation (TAVI) Trial) was a multicenter, randomized, clinical trial designed to evaluate the safety and efficacy of TAVI with or without balloon aortic valvuloplasty (BAV) in patients with symptomatic, severe aortic valve stenosis.

Purpose

To investigate by echocardiography the functional changes of self-expanding prosthetic valves during the first year after TAVI with or without BAV.

Methods

One hundred seventy one consecutive patients with severe aortic stenosis were enrolled at 4 centers and randomized to TAVI using self-expanding prostheses with (pre-BAV) or without pre-dilatation (no-BAV). Transthoracic echocardiography was obtained at baseline, 30 days and 1 year after TAVI.

Results

Of 171 patients, 86 patients were randomized to pre-BAV group and 85 to no-BAV group. Over the one year, 7 (4%) patients died and in 18 (10%) there was no available paired 30 day/1 year echo. At baseline echocardiography the peak and mean aortic valve gradient and the aortic valve area (AVA) in no-BAV group were 77.31±22.56 mmHg, 47.23±14.98 mmHg and 0.69±0.16cm2 and in pre-BAV group 81.97±23.17 mmHg, 49.39±14.78 mmHg and 0.65±0.15cm2 respectively. One year after TAVI, patients in no-BAV and pre-BAV group showed stable peak and mean aortic valve gradients similar to those at 30 days (from 16.36±7.88 to 14.51±6.6 mmHg vs. 17.17±8.88 to 15.95±9.97 mmHg and from 8.87±4.23 to 7.99±4.04 mmHg vs. 9.39±4.79 to 8.38±5.02 mmHg respectively, P<0.001 vs. baseline). The AVA was similarly stable in one year follow up in no-BAV group (from 1.85±0.43cm2 to 1.85±0.44cm2, P<0.001 vs. baseline) and in pre-BAV group (from 1.86±0.49cm2 to 1.84±0.39cm2, P<0.001 vs. baseline). The incidence of moderate or severe paravalvular regurgitation remained unchanged in both groups (from 4.7% to 5.7% in no-BAV group and from 5.8% to 6.6% in pre-BAV group).

Conclusions

In both pre-BAV and no-BAV groups the improvement in hemodynamics of self-expanding prosthetic valves remained durable during the one year echocardiographic follow up assessment.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): MEDTRONIC

No impact of direct implantation of a self-expanding valve on one-year clinical outcomes. Insights from the multicenter, randomized DIRECT trial

Introduction

The DIRECT trial (Predilatation in Transcatheter Aortic Valve Implantation Trial) evaluated in a randomized fashion the safety and efficacy of direct (without balloon pre-dilatation) implantation of a self-expanding valve in all comers undergoing TAVI.

Purpose

To investigate the impact of direct implantation of a self-expanding valve on one-year clinical outcomes.

Methods

DIRECT trial randomized consecutive patients with severe aortic stenosis at 4 tertiary centers to undergo TAVI with the use of self-expanding prostheses with (pre-BAV) or without pre-dilatation (no-BAV). The primary endpoint was device success according to the VARC-2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation and vascular complications.

All cause death, cardiac death, stroke and heart failure hospitalizations were recorded at one year and compared between the two groups using Kaplan-Meier plots.

Results

In total 171 patients were randomized in 4 centers. In the intention to treat analysis 86 patients were randomized to the pre-BAV group and 85 patients to the no-BAV TAVI group.

The device success according to the VARC-2 criteria was non-inferior in the no-BAV group compared to the pre-BAV group (65/85 - 76.5% for no-BAV versus 64/86 – 74.4% for pre-BAV, mean difference = 2.1%, 90% CI: −8.9 to 13). In the no-BAV group 25 (29.4%) patients underwent post balloon dilatation and in the pre-BAV group 13 patients (15.1%) (p=0.03).

At one year 4 deaths were recorded in pre-BAV group (4.7%) and 3 deaths in no-BAV group (3.5%). There was no difference in Kaplan-Meier plots between the two groups in all-cause mortality (log-rank p=0.72, figure). Similarly, there was no difference in one-year incidence of stroke (1 in pre-BAV and 2 in no-BAV group, log-rank p=0.55), cardiac death (log-rank p=0.66), non-cardiac death (log-rank p=0.98) and heart failure hospitalizations (1 in pre-BAV versus 3 in no-BAV group, log-rank p=0.31). Lastly, there was no difference in the incidence of permanent pacemaker implantation between the two groups at one year (27/67 in no-BAV group versus 20/69 in pre-BAV group, log-rank p=0.24)

Conclusions

Direct transcatheter aortic valve implantation is non-inferior to the procedure with pre-dilatation in self-expanding valve. Despite the overall low rate of events, direct procedure has no impact on clinical outcomes at one year.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Medtronic

P2724Diagnosis of transthyretin versus light chain cardiac amyloidosis by apical sparing strain ratio in patients with clinically suspected disease

Background

Apical sparing by longitudinal strain imaging has reported utility for the diagnosis of cardiac amyloidosis. However, potential differences in the apical sparing pattern in light chain (AL) versus transthyretin (ATTR) amyloidosis in patients with high clinical suspicion for cardiac amyloidosis is not clear.

Purpose

Our objective was to test the hypothesis that echocardiographic strain imaging could determine differences in patients with clinically suspected AL and ATTR cardiac amyloidosis.

Methods

We studied 206 patients, aged 64±11, with clinically suspected cardiac amyloidosis. Routine longitudinal strain imaging analyses was performed (EchoPAC, GE Healthcare) with bulls-eye plots. After 27 exclusions (8 arrhythmia/frame rate, 19 missing/poor images), there were 179 patients. Included were 129 patients with cardiac amyloid: 42 by endomyocardial biopsy, 4 by technetium pyrophosphate scan, 65 by non-cardiac biopsy with suggestive cardiac imaging (interventricular septal thickness ≥1.2cm by echocardiography or characteristic cardiac MRI findings), 15 with multiple myeloma and suggestive cardiac imaging, and 3 by autopsy; 50 patients had a negative endomyocardial biopsy or autopsy for cardiac amyloid. The apical sparing ratio by strain imaging was calculated as the (average of apical segments) / (average of mid segments + average of basal segments).

Results

Cardiac amyloidosis patients were 79% with AL and 21% with ATTR. Applying the previously published apical sparing ratio cut-off of 1.0 for longitudinal strain imaging, sensitivity and specificity were 29% and 78%, respectively, for diagnosis of cardiac amyloidosis. Applying a ratio cut-off of 0.81 improved sensitivity to 72% with specificity of 64% and area under the curve (AUC) of 0.66. Positive and negative predictive values were 85% and 46%, respectively, at this ratio cut-off. The apical sparing ratio was significantly higher in AL and ATTR as compared to the biopsy negative group (p<0.001). Furthermore, the apical sparing ratio was significantly higher in ATTR as compared to AL (p<0.05).

Apical sparing pattern and ratio

Conclusions

Among patients with high clinical suspicion for cardiac amyloidosis, the apical sparing ratio by echocardiographic strain imaging can demonstrate differences for AL and ATTR cardiac amyloidosis and has potential for clinical utility.

P5432Invasive assessment by atrial volume-pressure loops of the acute changes in left atrial function induced by pulmonary vein antral isolation

Background

Atrial volume-pressure loops are considered the best method to assess left atrium (LA) function. Changes in atrial function induced by pulmonary vein (PV) antral isolation of atrial fibrillation (AF) have not been documented thus far using this approach.

Purpose

We aimed to evaluate changes in LA function in patients with paroxysmal atrial fibrillation (PAF) undergoing catheter ablation by atrial volume-pressure loops.

Methods

Patients undergoing for the first time catheter ablation of PAF by PV antral isolation and PV-LA junction ablation, as clinically indicated, were enrolled from 2 centers. Each center enrolled consecutive patients undergoing PV antral isolation using the same method i.e. radiofrequency or cryoballoon ablation. Patients with severe mitral stenosis or regurgitation, any prosthetic valve, left atrial thrombus or severe systolic or diastolic dysfunction of the left ventricle were excluded. Before and after the procedure, all patients underwent real-time three-dimensional transthoracic echocardiogram to evaluate volume changes of the LA during an entire cardiac cycle, while simultaneously recording LA pressure by a 6F angiographic catheter following transseptal puncture. After the procedure, LA volume and pressure recordings were gated offline by ECG, and were used to plot the LA pressure as a function of LA volume, thus creating a volume-pressure loop. The A loop area is a measure of the booster pump function of the LA. The V loop area expresses the reservoir function of the LA. Pressure and volume data at the clockwise ascending limb of the volume-pressure loop were fitted to the exponential function P = bxea·V, where P = instantaneous LA pressure; V = LA volume; a is the passive elastic chamber stiffness constant (cm–3) that determines the slope of the exponential curve, and b is the elastic constant (mm Hg).

Results

34 patients with PAF were analysed, 12 treated with radiofrequency ablation and 22 with cryoablation. The procedure was uneventful in all cases. Mean LA pressure, A-wave amplitude, and V-wave amplitude were all significantly increased post-procedurally (p<0.001 for all). The area of the A-loop decreased (Post: 40.69 ml·mm Hg [IQR 13.7–71.3] vs. Pre: 64.2 ml·mm Hg [IQR 30.9–86.9]; p=0.001), whereas the area of the V-loop increased (Post: 96.5 ml·mm Hg [IQR 45.1–230.5] vs. Pre: 79.2 ml·mm Hg [IQR 46.9–149.7]; p=0.016). Although the elastic constant increased (p<0.001), there was no significant difference in the passive chamber elastic constant (p=0.30).

Conclusion

Volume-pressure loops can assess procedural changes in LA function. Catheter ablation of AF is associated with a decrease the LA booster pump function of the LA, and in increase in the left atrial reservoir function. Moreover, there is an increase in LA pressures that is observed in the absence of change in LA stiffness.

P1910Impact of pulmonary vein antral isolation by radiofrequency catheter or cryoballoon on left atrial function assessed by volume-pressure loops

Background

Atrial volume-pressure loops are used to assess left atrium (LA) function. Catheter ablation of paroxysmal atrial fibrillation (PAF) by pulmonary vein (PV) antral isolation can be performed either with radiofrequency (RF) catheter or with cryoballoon and might affect LA function.

Purpose

We explored a potential difference in changes in LA function by volume-pressure loops between patients with PAF undergoing either RF catheter or cryoballoon ablation.

Methods

Patients undergoing for the first time catheter ablation of PAF by PV antral isolation and PV-LA junction ablation, as clinically indicated, were enrolled from 2 centers. Each center enrolled consecutive patients undergoing PV antral isolation using the same method ie RF or cryoballoon ablation. Patients with severe mitral stenosis or regurgitation, any prosthetic valve, left atrial thrombus or severe systolic or diastolic dysfunction of the left ventricle were excluded. Pre and post procedure, all patients underwent real-time 3D transthoracic echocardiogram to evaluate volume changes of the LA during an entire cardiac cycle, while recording LA pressure by a 6F angiographic catheter following transseptal puncture. After the procedure, LA volume and pressure recordings were gated offline by ECG, and were used to plot the LA pressure as a function of LA volume, thus creating a volume-pressure loop. The A loop area is a measure of the LA booster pump function. The V loop area expresses the LA reservoir function. Pressure and volume data at the clockwise ascending limb of the volume-pressure loop were fitted to the exponential function P = bxea·V, where P = instantaneous LA pressure; V = LA volume; a is the passive elastic chamber stiffness constant (cm–3) that determines the slope of the exponential curve, and b is the elastic constant (mm Hg).

Results

34 patients with PAF were analysed, 12 treated with RF ablation and 22 with cryoablation. The procedure was uneventful in all cases. In the overall cohort, mean LA pressure, A-wave and V-wave amplitude were all increased post-procedurally (p<0.001); A-loop area decreased (p=0.001), whereas V-loop area increased (p=0.016). Although the elastic constant increased (p<0.001), there was no significant difference in the passive chamber elastic constant (p=0.30).

Changes in both A-loop and V-loop areas were similar between RF and cryoablation (p=0.18 and p=0.36, respectively). However, compared to cryoablation, RF ablation had a lower increase in the elastic constant (b=-2.24; 95% CI: −10.56 to −1.78), and a higher increase in the passive elastic chamber stiffness constant (b=0.078; 95% CI: 0.016 to 0.140).

Conclusion

Both in RF- and cryo-ablation and in a similar extent, the LA booster pump function is decreased, and LA reservoir function is increased. LA pressure is increased in RF ablation mainly due to an acute increase in LA stiffness, whereas in cryoablation this increase is observed in the absence of change in LA stiffness.

P3716Increased two-year cerebrovascular event rate in patients with bilateral high carotid tempratures

Introduction

The association of carotid plaque inflammation with cerebrovascular events is a matter of rigorous research. Microwave Radiometry (MWR) allows in vivo noninvasive measurement of the internal temperatures of tissues, reflecting inflammation.

Purpose

To investigate whether increased carotid temperatures in patients with documented coronary artery disease (CAD) are associated with cerebrovascular events.

Methods

Consecutive patients with significant CAD from three tertiary centers were included in the study. Maximum carotid plaque thickness was assessed in all carotids by ultrasound. ΔT by MWR was assigned as the temperature difference (maximal minus minimum) along the carotid artery. ΔT ≥0.90°C was assigned as high ΔT. All patients were followed-up clinically for two years and all strokes were adjudicated by an independent committee. Transient ischemic attacks were excluded.

Results

In total 300 patients were included in the study. High ΔT temperatures bilaterally were measured in 47 patients (15.7%). Three patients (1.0%) suffered a stroke, including one fatal. Stoke rate was 4.3% in the group with bilateral high ΔT and 0.4% in non-high ΔT group (p=0.02). In Kaplan-Meier plot patients with bilateral high ΔT showed higher stroke rate (log-rank p=0.004, figure)

Conclusions

Bilateral high carotid temperatures are associated with increased two-year stroke rate. The potential value of the present finding in risk stratification of intermediate carotid stenosis mandates further investigation.