Right atrial function in HFpEF in sinus rhythm vs. atrial fibrillation

Aims

We sought to study the prognostic impact of right atrial (RA) size and function in patients with heart failure with preserved ejection fraction (HFpEF) in sinus rhythm (SR) vs. atrial fibrillation (AF).

Methods and results

Consecutive HFpEF patients were enrolled and indexed RA volumes and emptying fractions (RA-EF) were assessed by cardiac magnetic resonance imaging (CMR). For patients in SR during CMR feature tracking of the RA wall was performed (Figure 1). In addition, all patients underwent right and left heart catheterization, 6 min walk test, and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) evaluation. We prospectively followed patients and used Cox regression models to determine the association of RA size and function with a composite endpoint of heart failure hospitalization and cardiovascular death. A total of 188 patients (71% female patients, 70±8 years old) were included of whom 96 (51%) were in SR. Eighty-five patients reached the combined endpoint during a follow-up of 72 (33–101) months. After multivariate cox regression analysis adjusted for age, NT-proBNP level, right ventricular ejection fraction and HF functional class, impaired RA strain (Figure 1A) (HR 0.959; 95% CI [0.924–0.996], P=0.024), RA conduit strain (Figure 1A) (HR 0.944; 95% CI [0.898–0.993], P=0.027) and RA conduit strain rate (Figure 1B) (HR 0.990; 95% CI [0.883–0.998], P=0.013) were significantly associated with adverse outcome for patients in SR (Table 1). In persistent AF, no RA imaging parameter was related to outcome after multivariate regression analysis.

Conclusions

In HFpEF patients in SR, CMR parameters of impaired RA conduit function show the best association with adverse cardiovascular outcome. In persistent AF, RA parameters lose their prognostic ability.

Funding Acknowledgement

Type of funding sources: None.

Right ventricular longitudinal strain on cardiovascular magnetic resonance imaging predicts outcome in patients undergoing transcatheter mitral valve repair

Background

The prognostic value of left and right ventricular global longitudinal strain (LV and RV GLS) derived from cardiovascular magnetic resonance (CMR) feature tracking in patients with severe mitral regurgitation (MR) undergoing transcatheter mitral valve repair (TMVR) is unknown.

Methods

Consecutive patients scheduled for TMVR underwent pre-procedural and follow-up CMR imaging including feature tracking strain analysis. Kaplan-Meier estimates and multivariate Cox-regression analyses were used to identify the prognostic impact of LV and RV GLS on CMR using a composite of heart failure hospitalization and death.

Results

A total of 62 patients (78.3±7.0y/o, 45% female, EuroSCORE II: 9.7±7.2%) with severe MR underwent CMR prior to TMVR. 23 (37%) patients presented with right ventricular dysfunction (RVD) defined by RV GLS >−20% on CMR. At baseline, RVD was associated with NT-proBNP levels (9510 vs. 4064pg/mL, p=0.030). On CMR, RVD was associated with reduced left and RV ejection fraction (LVEF: 39.2 vs. 48.7%, p=0.011, RVEF: 35.1 vs. 46.7%, p<0.001), as well as increased LV GLS (−14.0 vs. −19.5%, p=0.003).

A total of 18 events (12 deaths, 6 hospitalizations for heart failure) occurred during follow-up (mean 11.4±9.1months). While LV GLS was not significantly associated with outcome (HR 0.95, 95% CI: 0.90–1.01, p=0.082), RV GLS showed a strong and independent association with event-free survival by multivariate Cox-regression analysis (adj.HR 0.91, 95% CI: 0.83–0.99, p=0.033) after adjustment for relevant baseline and procedural data (EuroSCORE II, post-procedural residual MR), imaging parameters (TAPSE, LV and RVEF on CMR), and cardiac biomarkers (NT-proBNP). When compared with the “gold standard” RVEF on CMR (RVEF <45%: adj.HR 0.86, 95% CI: 0.23–3.20, p=0.825) and TAPSE on echo (TAPSE <17mm: adj.HR: 2.77, 95% CI: 0.72–10.70, p=0.140), only RVD (RV GLS >−20%: adj.HR 5.05, 95% CI: 1.23–20.63, p=0.024) was significantly associated with the composite endpoint (Figure 1). Follow-up CMR was performed in 21 (34%) patients. RV GLS significantly improved after TMVR (−20.6 to −25.2%, p=0.016, Figure 2).

Conclusions

RV rather than LV GLS, as determined on CMR, is an important predictor of outcome in patients undergoing TMVR. At 1 year follow-up, RV function significantly improved, and thus might add useful prognostic information on top of established risk factors.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Transcatheter versus surgical valve repair in patients with severe mitral regurgitation

Background

Transcatheter edge-to-edge mitral valve repair (TMVR) is increasingly performed, however, its efficacy in comparison with surgical MV treatment (SMV) is unknown.

Methods

Consecutive patients with severe mitral regurgitation (MR) undergoing TMVR (68% functional, 32% degenerative) or SMV (9% functional, 91% degenerative; 23% MV replacement) were enrolled. To account for differences in baseline characteristics, propensity score-matching including age, EuroSCORE-II, left ventricular ejection fraction, and NT-proBNP was performed. A composite of heart failure (HF) hospitalization/death was defined as primary endpoint. Kaplan-Meier curves and Cox-regression analyses were used to investigate associations between baseline, imaging, and procedural parameters and outcome.

Results

Between July 2017 and April 2020, 245 patients were enrolled, of which 102 patients could be adequately matched (73y/o, 61% females, EuroSCORE-II: 5.7%, p>0.05 for all). Despite matching, TMVR patients were sicker at baseline (higher rates of prior myocardial infarction, coronary revascularization, pacemakers/defibrillators, and diabetes mellitus, p<0.009 for all).

Patients were followed for 28.3±27.2 months, during which 27 events (17 deaths, 10 HF hospitalizations) occurred.Postprocedural MR reduction (MR grade <2: TMVR vs. SMV: 88% vs. 94%, p=0.487) and freedom from HF hospitalization/death (log-rank: p=0.221) were similar at two years. By multivariable Cox analyses, EuroSCORE-II (adj.HR 1.07 [95% CI: 1.00–1.13], p=0.027) and postprocedural MR severity (adj.HR 1.85 [95% CI: 1.17–2.92], p=0.009) emerged as independent predictors of outcome.

Conclusions

In this propensity matched, all-comers cohort, 2-year outcomes after TMVR versus SMV were similar. Given the reported favorable long-term durability of TMVR, the interventional approach emerges as valuable alternative for a substantial number of patients with functional and degenerative MR at high/prohibitive surgical risk.

Funding Acknowledgement

Type of funding sources: None.

131Left atrial phasic function in heart failure with preserved ejection fraction: cardiac magnetic resonance myocardial feature tracking, invasive hemodynamics and outcome

Background

Global left atrial (LA) size and function have been shown to be associated with adverse events in heart failure with preserved ejection fraction (HFpEF). The machanism of coupling from left heart failure to pulmonary circulation is still controversially discussed.

Purpose

To study the prognostic most relevant determinant of LA size and function and its backward and forward interplay.

Methods

188 HFpEF patients were prospectively enrolled and underwent baseline clinical assessment, cardiac magnetic resonance imaging (CMR) and invasive hemodynamic assessment. Coronary artery disease was ruled out by coronary angiography. 92 patients were in atrial fibrillation (AF), 96 in sinus rhythm. LA size and function were assessed by CMR including LA strain imaging by myocardial feature tracking (Figure 1A & B).

Results

Patients in AF had more pronounced dilatation of all phasic LA volumes and reduction of all phasic LA functions when compared to sinus rhythm (each p<0.001 respectively).

After 31 (9–57) months 66 patients reached the combined endpoint defined as combination from hospitalization due to heart failure and cardiovascular death. In AF no atrial functional or volume parameter was correlated to outcome. In contrast in sinus rhythm several phasic LA volume and functional parameters were associated with outcome. After multivariate cox regression analysis only reduced total LA ejection fraction and conduit strain rate were still predictive for worse outcome (p=0.031 and <0.001 respectively). After adjustment for known risk factors in HFpEF like age, six minute walking distance (6MWD), systolic pulmonary artery pressure (sPAP) and right ventricular ejection fraction as derived by CMR only impaired LA conduit strain rate remained predicitve for cardiovascular events (p=0.001). In contrast to LA booster pump function LA conduit function parameters were significantly correlated to reduced 6MWD (Figure 1C) and coupled backwards to pulmonary vasculature via correlation to sPAP and pulmonary vascular resistance (PVR) but without coupling to CMR derived elevated LV extracellular volume and left ventricular end diastolic pressure.

Conclusion

Total LA ejection fraction plays a key role in the prognosis of HFpEF. This effect seems to be mainly related to its LA conduit function but not to LA booster pump function. LA conduit function correlates to impaired 6MWD, sPAP and PVR.

P4128The right heart in patients undergoing transcatheter aortic valve replacement: insights from cardiac magnetic resonance imaging

Background

Cardiac magnetic resonance (CMR) provides the gold standard for the assessment of ventricular volumes and mass. However, data on right ventricular systolic dysfunction (RVSD) and its prognostic significance on outcome in patients undergoing transcatheter aortic valve replacement (TAVR) are lacking.

Methods

We consecutively enrolled patients with severe aortic stenosis scheduled for TAVR who underwent preprocedural CMR. Kaplan-Meier estimates and multivariate Cox-regression analysis were used to identify factors associated with outcome, including RVSD. A composite of heart failure hospitalization and/or cardiovascular death was selected as primary study endpoint.

Results

145 consecutive patients (80.5±7.6 years; 51.7% female) were prospectively included, 25 (17.2%) of which had RVSD defined as RV ejection fraction (RVEF) <40%. RVSD was significantly associated with male sex, atrial fibrillation, reduced left ventricular (LV) EF (<50%) and RV endsystolic volume on CMR (all p<0.05). Serum NT-proBNP (14065±12042 vs. 3203±4615 ng/ml; p<0.001) and creatinine levels (1.59±0.96 vs. 1.29±1.03 mg/dl; p=0.201) were elevated in patients with RVSD. A total of 27 events occurred during follow-up (29±13 weeks). While LVSD was not significantly associated with outcome (p=0.654), RVSD showed a strong and independent association with event-free survival in the multivariate Cox-regression analysis [hazard ratio 3.836 (95% confidence interval 1.670–8.810); p=0.002], which included all relevant CMR parameters, cardiovascular risk factors and routine biomarkers.

Conclusions

RVSD rather than LVSD, as determined by CMR, is an important predictor of outcome in patients undergoing TAVR. RV function might thus add useful prognostic information on top of established risk factors.