Left atrial pump strain predicts long-term survival after transcatheter aortic valve implantation

BACKGROUND

This study aims at investigating left atrial (LA) deformation by left atrial reservoir (LARS) and pump strain (LAPS) and its implications for long-term survival in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI).

METHODS

Speckle tracking echocardiography was performed in 198 patients with severe AS undergoing TAVI. Association of strain parameters with cardiovascular mortality was determined.

RESULTS

Over a follow-up time of 5 years, 49 patients (24.7%) died. LAPS was more impaired in non-survivors than survivors (P = 0.010), whereas no difference was found for LARS (P = 0.114), LA ejection fraction (P = 0.241), and LA volume index (P = 0.292). Kaplan-Meier analyses yielded a reduced survival probability according to the optimal threshold for LAPS (P = 0.002). A more impaired LAPS was associated with increased mortality risk (HR 1.12 [95% CI 1.02-1.22]; P = 0.014) independent of LVEF, LAVI, age, and sex. Addition of LAPS improved multivariable echocardiographic (LVEF, LAVI) and clinical (age, sex) models with potential incremental value for mortality prediction (P = 0.013 and P = 0.031, respectively). In contrast, LARS and LAVI were not associated with mortality.

CONCLUSIONS

In patients undergoing aortic valve replacement for severe AS, LAPS was impaired in patients dying during long-term follow-up after TAVI, differentiated survivors from non-survivors, was independently associated with long-term mortality, and yielded potential incremental value for survival prediction after TAVI. LAPS seems useful for risk stratification in severe AS and timely valve replacement.

Correlation between fluoroscopy and tomographic aortic-root measurements in the decision of the transcatheter heart valve size in patients undergoing transcatheter aortic valve implantation

Introduction and hypothesis

Transcatheter aortic valve implantation (TAVI) has become the standard treatment in intermediate and high-risk patients with high degree aortic stenosis (AS).(1–2) These has been also extended to low-risk and younger patients.(3–5) Besides the use of computed-tomography (CT) as diagnostic method to measure the aortic anatomy for transcatheter heart valve (THV) size decision and the radiation exposure (RE) during TAVI, younger patients are more exposed to radiation and contrast media (CM) complications due to a potentially second procedure.(6) Reducing RE and CM using only angiography aortic measurement could reduce the risk of RE and CM related complications without compromising the efficacy of the THV. We hypothesize that angiographic aortic root (AR) measure has good correlation with CT measure without compromising safety and efficacy of the THV.

Methods

Observational analysis: 1250 transfemoral TAVI patients with balloon or self-expandable valves were included. Aortic root CT measurement was done in all patients. AR measurement using Follow the right cup rule (7) was additionally done in 505 patients. Correlation between CT only (Group I n=745) versus CT and AR measurement (Group II n=505) was done. An inter and intraobserver validation analysis was done. Primary endpoint was VARC-2 device success. Secondary safety endpoints were composite of in-hospital and 30-days complications.

Results

Really good intra (0.86, p<0.001) and interobserver (0.81, p<0.001) correlation between CT (mean aortic diameter, distance between non (NC-HP) and left cusp hinge points (LC-HP) distance) and angiographic (LC-HP distance) measurements was observed. CT and AR measurement had a very good correlation between the two groups (CT mean aortic diameter vs CT NC-HP and LC-HP distance, 0.724 p<0.001; CT NC-HP and LC-HP distance vs angiographic NC-HP and LC-HP distance manual calibration 0.808 p<0.001; angiographic NC-HP and LC-HP distance manual calibration vs angiographic NC-HP and LC-HP distance automatic calibration 0.930 p<0.001). No differences in primary endpoint were observed between groups (device success Group I 98% vs Group II 99%, p 0.18). In-hospital complications were similar between two groups except in major bleeding (13% vs 19%, p 0.004), major vascular (10.9% vs 16.6%, p 0.004) and minor vascular (14% vs 21%, p 0.001) between group I and II respectively. Valve safety (86% vs 77%, p<0.001, OR 0.89, 95% CI 0.85–0.95) and clinical efficacy (84% vs 60.8%, p<0.001, OR 0.72, 95% CI 0.67–0.77) at 30 days were more common in group II. No difference in valve dysfunction was observed (Group I 10.3% vs Group II 7.3%, p 0.042, OR 1.41, 95% CI 0.97–2.05).

Conclusions

Compared to CT, AR measurement is a good option selecting THV size. No differences regarding device success and in-hospital and 30 days follow-up complications were observed. AR measurement could replace CT in specific cases.

Funding Acknowledgement

Type of funding sources: None. Angiographic and CT measurementsEndpoints

Mitral annular disjunction in patients with severe aortic stenosis: Extent and reproducibility of measurements with computed tomography

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Mitral annulus disjunction (MAD) is frequent in patients with severe aortic stenosis.

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Computed tomography enables a highly reproducible assessment of MAD.

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MAD patients significantly more often have mitral valve prolapse.

Objectives

To determine with CT the prevalence and extent of mitral annular disjunction (MAD) in patients undergoing transcatheter aortic valve replacement (TAVR) and its association with mitral valve disease and arrhythmia.

Methods

We retrospectively evaluated 408 patients (median age, 82 years; 186 females) with severe aortic stenosis undergoing ECG-gated cardiac CT with end-systolic data acquisition. Baseline and follow-up data were collected in the context of a national registry. Two blinded, independent observers evaluated the presence of MAD on multi-planar reformations. Maximum MAD distance (left atrial wall-mitral leaflet junction to left ventricular myocardium) and circumferential extent of MAD were assessed on CT using dedicated post-processing software. Associated mitral valve disease was determined with echocardiography.

Results

7.8 % (32/408) of patients with severe aortic stenosis had MAD. The maximum MAD was 3.5 mm (interquartile range: 3.0–4.0 mm). The circumferential extent of MAD comprised 34 ± 15 % of the posterior and 26 ± 12 % of the entire mitral annulus. Intra- and interobserver agreement for the detection of MAD on CT were excellent (kappa: 0.90 ± 0.02 and 0.92 ± 0.02). Mitral regurgitation (p = 1.00) and severe mitral annular calcification (p = 0.29) were similarly prevalent in MAD and non-MAD patients. Significantly more patients with MAD (6/32; 19 %) had mitral valve prolapse compared to those without (6/376; 2 %; p < 0.001). MAD was not associated with arrhythmia before and after TAVR (p > 0.05).

Conclusions

Using CT, MAD was found in 7.8 % of patients with severe aortic stenosis, with a higher prevalence in patients with mitral valve prolapse. We found no association of MAD with arrhythmia before or after TAVR.

Mitral annular calcification in the elderly - Quantitative assessment

PURPOSE

To determine the reliability of subjective and objective quantification of mitral annular calcification (MAC) in elderly patients with severe aortic stenosis, to define quantitative sex- and age-related reference values of MAC, and to correlate quantitative MAC with mitral valve disease.

METHODS

In this retrospective, IRB-approved study, we included 559 patients (268 females, median age 81 years, inter-quartile range 77-85 years) with severe aortic stenosis undergoing CT. Four independent readers performed subjective MAC categorization as follows: no, mild, moderate, and severe MAC. Two independent readers performed quantitative evaluation of MAC using the Agatston score method (Agatston_MAC). Mitral valve disease was determined by echocardiography.

RESULTS

Subjective MAC categorization showed high inter-reader agreement for no (k ​= ​0.88) and severe MAC (k ​= ​0.75), whereas agreement for moderate (k ​= ​0.59) and mild (k ​= ​0.45) MAC was moderate. Intra-reader agreement for subjective MAC categorization was substantial (k ​= ​0.69 and 0.62). Inter- and intra-reader agreement for Agatston_MAC were excellent (ICC ​= ​0.998 and 0.999, respectively), with minor inconsistencies in MAC involving the left ventricular outflow tract/aortic valve. There were significantly more women than men with MAC (n ​= ​227, 85% versus n ​= ​209, 72%; p ​< ​0.001), with a significantly higher Agatston_MAC (median 597, range 81-2055 versus median 244; range 0-1565; p ​< ​0.001), particularly in patients ≥85 years of age. Agatston_MAC showed an area-under-the-curve of 0.84 to diagnose mitral stenosis, whereas there was no association of Agatston_MAC with mitral regurgitation (p ​> ​0.05).

CONCLUSIONS

Our study in elderly patients with severe aortic stenosis shows that quantitative MAC scoring is more reliable than subjective MAC assessment. Women show higher Agatston_MAC scores than men, particularly in the elderly population. Agatston_MAC shows high accuracy to diagnose mitral stenosis.

Bending the Rules in Transfemoral TAVI With the SAPIEN 3: Overcoming Severe Iliac Tortuosity

Whilst the worldwide uptake of transcatheter aortic valve implantation (TAVI) over the last 10 years has been dramatic, iliac tortuosity remains a potential barrier to the most commonly chosen access route via the femoral artery. We describe the challenges posed by severe iliac tortuosity during transfemoral TAVI and contrast a difficult procedure - at the limit of the capability of current device delivery technology - with a straightforward implantation. The use of pre-procedural multi-detector computed tomography to assess the vasculature and a bilateral stiff wire technique for managing iliofemoral tortuosity are discussed.

Delayed response of myocardial flow reserve to lipid-lowering therapy with fluvastatin

BACKGROUND

Lipid-lowering therapy can improve endothelial function in patients with coronary artery disease (CAD) and hypercholesterolemia. Little is known about induced changes in myocardial microcirculation. This study prospectively investigated the temporal effects of lipid-lowering therapy with fluvastatin on coronary flow and flow reserve (CFR) in patients with CAD assessed by PET.

METHODS AND RESULTS

In an open clinical trial, CFR was studied in 15 patients with angiographically documented multivessel CAD and hypercholesterolemia (LDL >160 mg/dL). Dynamic 13N-labeled ammonia PET imaging in conjunction with adenosine was used to assess regional and global CFR at baseline as well as at 2 and 6 months during treatment with fluvastatin (60 to 80 mg/d). Despite a rapid decrease in total cholesterol (29+/-6%) and LDL (37+/-9%), myocardial blood flow at rest and during stress was unchanged after 2 months of treatment (2.7+/-0.9 versus 2.5+/-0.6 mL x g-1 x min-1). At 6 months, stress blood flow as well as CFR increased significantly (3.4+/-1.0 mL x g-1 x min-1). No change in hemodynamic parameters was noted during the entire study. Nine of 15 patients increased CFR by >20%. All responders demonstrated improvement in anginal symptoms, whereas nonresponders stated no change (n=4) or worsening of symptoms (n=2). The improvement in CFR was not related to the amount of lipid lowering and was independent of the severity of stenoses.

CONCLUSIONS

Improvement in stress blood flow and CFR is delayed compared with the lipid-lowering effect of fluvastatin, suggesting a slow recovery of the vasodilatory response to adenosine.

B2 bradykinin receptors in cultured neonatal rat cardiomyocytes mediate a negative chronotropic and negative inotropic response

Receptors for bradykinin (BK) were characterized in primary cultures of beating neonatal rat cardiomyocytes using [3H]BK was radioligand. Degradation studies demonstrated that [3H]BK was stable for at least 2 h when incubated with cardiomyocytes at 2 and 37 degrees C in the presence of bacitracin in combination with captopril or ramiprilat. Without these inhibitors, > 80% of the [3H]BK was degraded within 2 h at 37 degrees C. This indicates that angiotensin-converting enzyme (ACE) is responsible for the main BK-degrading activity in cardiomyocytes. Scatchard plots were linear and gave a Kd of 1.5 +/- 0.8 nmol/l (mean +/- SD, n = 4) and a maximum binding capacity of 55-125 fmol/mg protein. Association and dissociation studies showed that binding of [3H]BK was saturable and reversible. Binding of [3H]BK at 37 degrees C led to internalization of the ligand. Competition studies with B1 and B2 agonists and antagonists were consistent with a B2 subtype of receptor. Addition of BK to beating cardiomyocytes (> 1 nmol/l) at 37 degrees C gave a strong but transient negative chronotropic effect. This response was paralleled by changes in the pulsation amplitude, which indicated a simultaneous negative inotropic effect of BK. These results provide a basis for the hypothesis that ACE inhibition exerts its cardioprotective effect at the level of a population of cardiomyocytes by virtue of kinin receptor-mediated mechanisms.