Left atrial dysfunction in patients with prosthesis-patient mismatch after transcatheter aortic valve replacement

Funding Acknowledgements

Type of funding sources: None.

Background. Transcatheter aortic valve replacement (TAVR) prostheses have better hemodynamics compared to surgical prostheses, with lower incidence of prosthesis-patient mismatch (PPM). Nonetheless, this complication is neither rare nor benign in the expanding population of TAVR patients (pts). Data regarding the effect of TAVR PPM on cardiac function is scarce. Our aim was to determine the short-term impact of PPM on left atrium (LA) function in patients undergoing transfemoral TAVR.

Methods. One hundred forty-three consecutive pts (76.3 ± 7.5 yrs, 74 men) considered to be at high risk for SAVR were enrolled and examined before and 30 days after TAVR. All pts underwent a comprehensive echocardiogram, including speckle tracking echocardiography (STE) for LA and left ventricular (LV) strain analysis. Longitudinal LA strain parameters were assessed from the apical 4-chamber view. Peak values of global longitudinal LA strain (LAε) and LA systolic strain rate (SSr, reservoir function) and early diastolic strain rate (ESr, conduit function) were measured in all. Contractile LA function (late diastolic strain rate, ASr) was assessed in patients in sinus rhythm (106 pts).

Results. Fifty-five pts (38%) had PPM (defined as an indexed effective orifice area, EOA ≤0.85 cm2/m2). Most of these pts (71%) had moderate PPM (indexed EOA between 0.65 and 0.85 cm2/m2). No significant differences in age (76.4 ± 8.1 vs 76.3 ± 7.2 yrs, p = 0.9), gender (p = 0.2), body surface area (p = 0.8), body mass index (p = 0.2) and the presence of cardiovascular risk factors (p > 0.2 for all) were observed between pts with and without PPM. The severity of post-TAVR aortic regurgitation was mild in 92 pts (64%) and moderate in 12 pts (8%) without any significant difference between pts with and without PPM. The post-TAVR prevalence of ³moderate mitral regurgitation was not different between the two groups (p = 0.40). After TAVR, there were no significant differences in terms of indexed LV mass, volumes, ejection fraction (p > 0.5 for all). LV global longitudinal strain was also similar between groups (-13.7 ± 4.3 vs -14 ± 3.6%, p = 0.7). Although LA volumes were similar between patients with and without PPM (47.8 ± 12.4 vs 49.3 ± 20.3 ml/m2, p = 0.6), in the mismatch-group we found a significantly reduced systolic global LA strain (12.7 ± 6.2 vs 15.9 ± 7.9%, p = 0.009) and impaired LA contractile function (ASr: -1.0 ± 0.4 vs -1.2 ± 0.5, p = 0.03). Parameters of LV diastolic function were also worse in the mismatch-group, with an E/e’sep ratio of 22 ± 10 vs 17 ± 7, p = 0.01.

Conclusions. In our study group TAVR was associated with an incidence of PPM of 38%. The short-term follow-up of these patients revealed a significantly impaired LA function and increased LV filling pressure in patients with PPM compared to those without PPM. To our knowledge, this is the first report about the effect of PPM on the LA global and contractile function.

P301 The prognostic value of preoperative left atrial volume after surgical aortic valve replacement in patients with isolated severe aortic stenosis and preserved left ventricular ejection fraction

Background

Left atrial (LA) volume is an important cardiovascular prognostic marker. However, data regarding the prognostic value of LA volume in severe AS patients (pts) after surgical aortic valve replacement (AVR) are scarce. Moreover, the predictive role of LA function in AS pts after AVR has not yet been studied. Our study aimed to assess the relationship of LA volume index (LAVi) and function with outcome, in terms of mortality, in severe AS pts who underwent surgical AVR.

Methods

A total of 360 consecutive pts with isolated severe AS (aortic valve area index ≤ 0.6 cm2/m2) referred to our echocardiography laboratory were prospectively screened. Two hundred and seventeen pts with preserved left ventricular (LV) ejection fraction (≥50%) and in sinus rhythm were enrolled. All patients underwent a baseline comprehensive echocardiogram, including speckle tracking analysis of both LV and LA strain. Symptomatic pts (142 pts, 65%) that were subject to AVR were followed for a median period of 4 years (IQR 3-6 years). The endpoint was all-cause mortality after AVR. The last update of the survival status was obtained in January 2019. Outcome data were available in 116 severe AS pts that underwent AVR (mean age 63 ± 10 yrs, 56% men), who formed the final study population.

Results

Seventeen (14%) pts died during follow-up. No significant differences were found between nonsurvivors and survivors after AVR in terms of age and cardiovascular risk factors. Nonsurvivors had higher BNP plasma values (p=.04) at baseline compared with surviving pts. Survivors and nonsurvivors alike exhibited similar preoperative AS severity and LV systolic function parameters (ejection fraction and global longitudinal strain). Moreover, there were no significant differences between the two groups regarding baseline valvuloarterial impedance, average E/e’ ratio, and LA longitudinal deformation parameters. Nonsurvivors had a tendency toward higher LV mass index (p=.08). Nonsurvivors had higher preoperative LA volume index (LAVi)(50 ± 12 vs. 44 ± 10 ml/m2, p=.003). In a multivariable Cox regression analysis adjusted for age, LAVi emerged as the only independent predictor for death in our population study (HR 1.06, 95% CI 1.01-1.11, p=.02). A cut-off value for LAVi derived from ROC curve analysis was used to construct Kaplan-Meier survival curves. A value of 43 ml/m2 for LAVi predicted all-cause mortality after AVR in severe AS pts with 71% sensitivity and 54% specificity.

Conclusions

In our study, preoperative LAVi predicted death in severe AS pts after surgical AVR. LAVi assessment may improve preoperative risk stratification in patients with severe AS, however further larger prospective studies are needed.

Abstract P301 Figure.

621 Anemia and its impact on clinical, echocardiographic parameters and prognosis in patients with severe aortic stenosis and normal left ventricular ejection fraction

Background

Anemia is common in patients (pts) with severe aortic stenosis (AS). Untreated anemia and severe AS are individually associated with the development of heart failure, however data regarding the potential detrimental effect of anemia on left ventricular (LV) function and prognosis in pts with severe AS are controversial.

Aim

To investigate the impact of anemia on clinical status, echocardiographic parameters and prognosis in pts with severe AS and preserved LV ejection fraction (LVEF).

Methods

Consecutive patients with severe AS (aortic valve area [AVA] index ≤ 0.6 cm2/m2) and preserved LVEF (>50%) referred to our echocardiography laboratory were prospectively screened. All patients underwent complete clinical examination and comprehensive echocardiography, including speckle tracking-derived measurements of LV and left atrial (LA) strain. Baseline clinical variables included NYHA class, cardiac risk factors, haemoglobin (Hb) level and glomerular filtration rates (GFR, by MDRD formula). The definition of anemia was based on gender-specific cut-off values, as recommended by the WHO (Hb <13.0 g/dL for men, <12.0 g/dL for women). Patients with more than mild aortic regurgitation or mitral valve disease, atrial fibrillation or cardiac pacemakers were excluded.

Results

The study population included 264 patients (pts) (66 ± 11 yrs, 147 men). Anemia was present in 64 pts (24%). Aortic valve replacement (AVR) was performed in 151 pts. Dividing the study population into 2 groups, according to the presence/absence of anemia, no significant differences were found between groups regarding: age (p = 0.09), body surface area (p = 0.6), LVEF (62 ± 7 vs 63 ± 6%, p = 0.2), LV Global Longitudinal Strain (-15.2 ± 4 vs -14.7 ± 3 %, p = 0.4), LV mass index (p = 0.9), mean aortic gradient (p = 0.2) and indexed AVA (0.40 ± 0.09 vs 0.39 ± 0.09 cm2/m2, p = 0.6), or presence of significant coronary artery disease (p = 0.9). Compared to pts with normal Hb level, in pts with anemia NYHA class (p = 0.03), brain natriuretic peptide values (p = 0.004), lateral E/e’(16.2 ± 6.9 vs 13.7 ± 6.3, p = 0.01) and average E/e" ratio (15.9 ± 5.9 vs 14.1 ± 5.3, p = 0.03), LA volume index (54.3 ± 16.9 vs 45.0 ± 12.1 ml/m2, p < 0.001), and systolic pulmonary artery pressure (38 ± 13 vs 33 ± 8, p = 0.009) were all significantly higher. During a 3–years follow-up 47 pts died. Age, NYHA class, BNP serum level, baseline anemia, LA volume index and systolic pulmonary pressure were associated with all-cause mortality in the whole study group (p < 0.03 for all). In the group of pts who underwent AVR, NYHA class was the only independent predictor of all-cause mortality.

Conclusions

In our study including pts with severe AS and preserved LVEF, patients with baseline anemia presented worse functional status and LV diastolic dysfunction and increased 3-year all-cause mortality compared to those with normal Hb levels. However, in pts who underwent surgical AVR, there was no impact of baseline anemia on 3-year survival.

Surgical Management of Type A Acute Aortic Dissection in Patients With Marfan Syndrome: A Single Center Experience

Introduction: Acute aortic dissection is the most common cause of death in patients with Marfan syndrome and untreated aortic root enlargement. Emergency surgery for replacement of the ascending aorta has the potential of life saving procedure, but is associated with high morbidity and mortality. Long-term outcomes after surgical repair of acute aortic dissection type A in patients with Marfan syndrome are limited. Material and methods: We made a retrospective study concerning emergency surgical intervention for acute aortic dissection type A, by Bentall procedure, performed in Emergency Institute for Cardiovascular Diseases „Prof dr. C. C. Iliescu” Bucharest between January 2005 and July 2014. We included 332 patients with type a acute aortic dissection divided into two groups: group A - 16 patients with Marfan syndrome and group B - 316 patients with other etiologies. We analyzed differences between these two groups regarding perioperative characteristics, surgical technique and short and long-term morbidity and mortality. Results: The patients from group A were significantly younger than those in group B (35.1±12.7 years vs. 56.8±7.1 years; p<0.001). Arterial hypertension was three times more common in group B as compared to group A (p<0.001). The incidence of postoperative morbidity, and intraoperative and 30-days mortality death rates were similar between groups, but overall mortality at 10 years was lower in group A (31.3%) vs. group B (44.9 %). Conclusions: Emergency surgical in Marfan syndrome, by Bentall procedure could improve perioperative morbidity and mortality of patients with acute aortic dissection, but need an early diagnosis, proper medical therapy and imagistic surveillance.