Enriquez‐Sarano, Maurice

Background: Functional tricuspid regurgitation (FTR) is common in heart failure with reduced ejection fraction and mostly consequent to pulmonary hypertension. However, the intrinsic clinical implications of FTR are not fully understood. Methods: The cohort of all Mayo Clinic patients from 2003 to 2011 diagnosed with heart failure stage B-C and ejection fraction<50%, with FTR grading and systolic pulmonary artery pressure estimation by Doppler echocardiography was identified and outcomes were analyzed. Patients with pacemakers/defibrillators, organic valve disease, or previous valve surgery were excluded. The primary outcome measure was overall mortality (censored at implantation of a defibrillator, ventricular assist device, or cardiac transplantation), adjusting for clinical and echocardiographic associates with mortality and major comorbidities. Results: Among 13 026 patients meeting inclusion criteria, FTR was detected in 88% (N=11 507: 33% trivial, 32% mild, 17% moderate, and 6% severe), aged 68±14 years, 35% women, ejection fraction 36±10%, systolic pulmonary artery pressure 41±14 mm Hg with 20% atrial fibrillation. Covariates independently associated with FTR included elevated systolic pulmonary artery pressure, older age, female sex, lower ejection fraction, mitral regurgitation, and atrial fibrillation (all P <0.0001). FTR was independently associated with more dyspnea, impaired kidney function, and lower cardiac output ( P <0.003 for all). For long-term outcome, higher FTR degree compared with trivial tricuspid regurgitation was independently associated with higher mortality (adjusted hazard ratios 1.09 [1.01-1.17] for mild FTR, 1.21 [1.11-1.33] for moderate FTR and 1.57 [1.39-1.78] for severe FTR); hence, 5-year survival was substantially lower with increasing severity of functional FTR, 68±1% for trivial FTR, 58±2% for mild FTR, 45±2% for moderate FTR, and 34±4% for severe FTR. Conclusions: In this large cohort of patients with heart failure with reduced ejection fraction, FTR was common and independently associated with pulmonary hypertension, atrial fibrillation, and more severe heart failure presentation. Long-term, higher FTR severity is associated with considerably worse survival, independently of baseline characteristics. Given these untoward outcomes associated with FTR in patients with heart failure with reduced ejection fraction, clinical trials should be directed at testing FTR treatment.

Abstract Aims To define the hitherto unknown aetiology/mechanism distributions of mitral regurgitation (MR) in the community and the linked clinical characteristics/outcomes. Methods and results We identified all isolated, moderate/severe MR diagnosed in our community (Olmsted County, MN, USA) between 2000 and 2010 and classified MR aetiology/mechanisms. Eligible patients (n = 727) were 73 ± 18 years, 51% females, with ejection fraction (EF) 49 ± 17%. MR was functional (FMR) in 65%, organic (OMR) in 32% and 2% mixed. Functional MR was linked to left ventricular remodelling (FMR-v) 38% and isolated atrial dilatation (FMR-a) 27%. At diagnosis FMR-v vs. FMR-a, vs. OMR displayed profound differences (all P &lt; 0.0001) in age (73 ± 14, 80 ± 10, 68 ± 21years), male-sex (59, 33, 51%), atrial-fibrillation (28, 54, 13%), EF (33 ± 14, 57 ± 11, 61 ± 10%), and regurgitant-volume (38 ± 13, 37 ± 11, 51 ± 24 mL/beat). Dominant MR mechanism was Type I (normal valve-movement) 38%, Type II (excessive valve-movement) 25%, Type IIIa (diastolic movement-restriction) 3%, and Type IIIb (systolic movement-restriction) 34%. Outcomes were mediocre with excess-mortality vs. general-population in FMR-v [risk ratio 3.45 (2.98–3.99), P &lt; 0.0001] but also FMR-a [risk ratio 1.88 (1.52–2.25), P &lt; 0.0001] and OMR [risk ratio 1.83 (1.50–2.22), P &lt; 0.0001]. Heart failure was frequent, particularly in FMR-v (5-year 83 ± 3% vs. 59 ± 4% FMR-a, 40 ± 3% OMR, P &lt; 0.0001). Mitral surgery during patients’ lifetime was performed in 4% of FMR-v, 3% of FMR-a, and 37% of OMR. Conclusion Moderate/severe isolated MR in the community displays considerable aetiology/mechanism heterogeneity. Functional MR dominates, mostly FMR-v but FMR-a is frequent and degenerative MR dominates OMR. Outcomes are mediocre with excess-mortality particularly with FMR-v but FMR-a, despite normal EF incurs notable excess-mortality and frequent heart failure. Pervasive undertreatment warrants clinical trials of therapies tailored to specific MR cause/mechanisms.

AbstractAimsMechanisms of chronic ischaemic mitral regurgitation (IMR) are well-characterized by apically tethered leaflet caused by papillary muscles (PMs) displacement and adynamic mitral apparatus. We investigated the unique geometry and dynamics of the mitral apparatus in first acute myocardial infarction (MI) by using quantified 3D echocardiography.Methods and resultsWe prospectively performed 3D echocardiography 2.3 ± 1.8 days after first MI, in 174 matched patients with (n = 87) and without IMR (n = 87). 3D echocardiography of left ventricular (LV) volumes and of mitral apparatus dynamics throughout cardiac cycle was quantified. Similar mitral quantification was obtained at chronic post-MI stage (n = 44). Mechanistically, acute IMR was associated with larger and flatter annulus (area 9.29 ± 1.74 cm2 vs. 8.57 ± 1.94 cm2, P = 0.002, saddle shape 12.7 ± 4.5% vs. 15.0 ± 4.6%, P = 0.001), and larger tenting (length 6.36 ± 1.78 mm vs. 5.60 ± 1.55 mm, P = 0.003) but vs. chronic MI, mitral apparatus displayed smaller alterations (all P < 0.01) and annular size, PM movement remained dynamic (all P < 0.01). Specific to acute IMR, without PM apical displacement (P > 0.70), greater separation (21.7 ± 4.9 mm vs. 20.0 ± 3.4 mm, P = 0.01), and widest angulation of PM (38.4 ± 6.2° for moderate vs. 33.5 ± 7.3° for mild vs. 31.4 ± 6.3° for no-IMR, P = 0.0009) wider vs. chronic MI (P < 0.01).Conclusions3D echocardiography of patients with first MI provides insights into unique 4D dynamics of the mitral apparatus in acute IMR. Mitral apparatus remained dynamic in acute MI and distinct IMR mechanism in acute MI is not PM displacement seen in chronic IMR but separation and excess angulation of PM deforming the mitral valve, probably because of sudden-onset regional wall motion abnormality without apparent global LV remodelling. This specific mechanism should be considered in novel therapeutic strategies for IMR complicating acute MI.