Natural history of echocardiographic changes in atrial fibrillation: A case-controlled study of longitudinal remodeling.

BACKGROUND: Atrial fibrillation (AF) can be a cause and consequence of cardiac remodeling. The natural history of remodeling associated with AF is incompletely described. OBJECTIVE: The purpose of this study was to describe the frequency and timing of AF-associated echocardiographic changes. METHODS: Patients within the Duke University Health System with ≥2 transthoracic echocardiograms (TTEs) performed between 2005 and 2018 were evaluated. Patients with AF and normal baseline TTEs were matched to patients without AF on year of TTE, age, and CHA2DS2-VASc score. Frequency and timing of changes in chamber size, ventricular function, mitral regurgitation, and all-cause mortality were compared over 5 years of follow-up. RESULTS: The cohort included 3299 patients with AF at baseline and 7613 controls without AF. Normal baseline TTEs were acquired from 730 of patients with AF; 727 of these patients were matched to controls without AF. Patients with AF had higher rates of left atrial enlargement (hazard ratio [HR] 1.53; 95% confidence interval 1.27-1.85; P < .001), left ventricular (LV) systolic dysfunction (HR 1.80; 95% confidence interval 1.00-3.26; P = .045), LV diastolic dysfunction (HR 1.51; 95% confidence interval 1.08-2.10; P = .01), and moderate or greater mitral regurgitation (HR 2.09; 95% confidence interval 1.27-3.43; P = .003) than did controls. Atrial enlargement, systolic dysfunction, and mitral regurgitation surpassed the rates seen in controls within 6-12 months, whereas differences in diastolic dysfunction emerged at 24 months. There were no differences in ventricular sizes or mortality. CONCLUSION: AF is associated with higher rates of left atrial enlargement, LV systolic and diastolic dysfunction, and mitral regurgitation that typically manifest within 6-24 months of diagnosis. The natural history of cardiac remodeling in patients with AF may inform treatment decisions and facilitate patient-tailored care.

Risk of Surgical Mitral Valve Repair for Primary Mitral Regurgitation.

BACKGROUND: Risk estimation for surgical intervention is an essential component of heart team shared decision-making. However, current mitral valve (MV) surgery risk models used in practice lack etiologic or procedural specificity. OBJECTIVES: The purpose of this study was to establish a comprehensive method for assessment of operative risk of MV repair of primary mitral regurgitation (MR). METHODS: A novel etiology and procedure-specific algorithm identified 53,462 consecutive (July 2014 to June 2020) intention-to-treat MV repair patients with primary MR from The Society of Thoracic Surgeons Adult Cardiac Surgery Database. Risk models were fit for 30-day operative mortality, mortality and/or major morbidity, and conversion-to-replacement (CONV). As-treated mortality and morbidity models were derived separately. RESULTS: Event rates for mortality (n = 619; 1.16%), mortality plus morbidity (n = 4,746; 8.88%), and CONV (n = 3,399; 6.36%) were low. Mortality was higher in CONV patients vs repair (3.18% vs 1.02%). All event rates were lower with increasing program volumes. The mortality risk model had excellent discrimination (AUC: 0.807) and calibration and confirmed very low mortality risk for isolated MV repair for primary MR, with mean mortality risk of 1.16% and median of 0.55% (IQR: 0.30%-1.17%) with 90th and 95th percentiles 2.48% and 3.99%, respectively. The mortality risk was <0.5% in patients <65 years of age, with 97% of the total population across age groups having a risk of <3%. Only 1 in 4 patients age 75 or older had >3% estimated risk of mortality. CONCLUSIONS: This etiologic and procedure-specific risk model establishes that the contemporary mortality risk of MV repair for primary MR is <1% for the vast majority of patients.

Risk of Surgical Mitral Valve Repair for Primary Mitral Regurgitation.

BACKGROUND: Risk estimation for surgical intervention is an essential component of heart team shared decision-making. However, current mitral valve (MV) surgery risk models used in practice lack etiologic or procedural specificity. The purpose of this study was to establish a comprehensive method for assessment of operative risk of MV repair of primary mitral regurgitation (MR). METHODS: A novel etiology and procedure-specific algorithm identified 53,462 consecutive (July 2014 to June 2020) intention-to-treat MV repair patients with primary MR from The Society of Thoracic Surgeons Adult Cardiac Surgery Database. Risk models were fit for 30-day operative mortality, mortality and/or major morbidity, and conversion-to-replacement (CONV). As-treated mortality and morbidity models were derived separately. RESULTS: Event rates for mortality (n = 619; 1.16%), mortality plus morbidity (n = 4746; 8.88%), and CONV (n = 3399; 6.36%) were low. Mortality was higher in CONV patients vs repair (3.18% vs 1.02%). All event rates were lower with increasing program volumes. The mortality risk model had excellent discrimination (AUC: 0.807) and calibration and confirmed very low mortality risk for isolated MV repair for primary MR, with mean mortality risk of 1.16% and median of 0.55% (interquartile range: 0.30%-1.17%) with 90th and 95th percentiles 2.48% and 3.99%, respectively. The mortality risk was <0.5% in patients <65 years of age, with 97% of the total population across age groups having a risk of <3%. Only 1 in 4 patients age 75 or older had >3% estimated risk of mortality. CONCLUSIONS: This etiologic and procedure-specific risk model establishes that the contemporary mortality risk of MV repair for primary MR is <1% for the vast majority of patients.

Transcatheter Edge-to-Edge Mitral Valve Repair in Patients With Severe Mitral Regurgitation and Cardiogenic Shock.

BACKGROUND: Data on the efficacy of transcatheter edge-to-edge repair (TEER) in patients with cardiogenic shock (CS) are limited. OBJECTIVES: This study investigated the characteristics and outcomes of consecutive patients with significant mitral regurgitation (MR) and CS who underwent TEER. METHODS: The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry was assessed from November 22, 2013, to December 31, 2021. CS was defined as the coding of: 1) CS; 2) inotrope use; or 3) mechanical circulatory support before TEER. Device success was defined as MR reduction of ≥1 grade and a final MR grade ≤2+. The primary outcome was the impact of device success on 1-year mortality or heart failure (HF) readmissions. Cox proportional hazards models were used to report the risk-adjusted association between device success and 1-year outcomes. RESULTS: A total of 3,797 patients met the inclusion criteria. Mean age was 73.0 ± 11.9 years, and 59.5% were male. Mean Society of Thoracic Surgery score (MV repair) was 14.9% ± 15.3%. MR etiology was degenerative (53.4%) and functional (27.5%). Device success was achieved in 3,249 (85.6%) patients given successful achievement of final MR grade ≤2+ (88.2%) and MR reduction ≥1 absolute grade (91.4%). At 1 year after TEER, device success was associated with significantly lower all-cause mortality (34.6% vs 55.5%; adjusted HR: 0.49; 95% CI: 0.41-0.59; P < 0.001) and a composite of mortality or HF admissions (29.6% vs 45.2%; adjusted HR: 0.51; 95% CI: 0.42-0.62; P < 0.001). CONCLUSIONS: Successful MR reduction is achievable in most patients with CS and is associated with significantly lower mortality and HF hospitalization at 1 year. Randomized trials assessing TEER in CS are needed to establish this potential therapeutic approach.

Association of Volume and Outcomes in 234 556 Patients Undergoing Surgical Aortic Valve Replacement.

BACKGROUND: The relationship between institutional volume and operative mortality after surgical aortic valve replacement (SAVR) remains unclear. METHODS: From January 2013 to June 2018, 234 556 patients underwent isolated SAVR (n = 144 177) or SAVR with coronary artery bypass grafting (CABG) (n = 90 379) within the Society of Thoracic Surgeons Adult Cardiac Surgery Database. The association between annualized SAVR volume (group 1 [1-25 SAVRs], group 2 [26-50 SAVRs], group 3 [51-100 SAVRs], and group 4 [>100 SAVRs]) and operative mortality and composite major morbidity or mortality was assessed. Random effects models were used to evaluate whether historical (2013-2015) SAVR volume or risk-adjusted outcomes explained future (2016-2018) risk-adjusted outcomes. RESULTS: The annualized median number of SAVRs per site was 35 (interquartile range, 22-59; isolated aortic valve replacement [AVR], 20; AVR with CABG, 13). Among isolated SAVR cases, the mean operative mortality and composite morbidity or mortality were 1.5% and 9.7%, respectively, at the highest-volume sites (group 4), with significantly higher rates among progressively lower-volume groups (P trend < .001). After adjustment, lower-volume centers had increased odds of operative mortality (group 1 vs group 4 [reference]: adjusted odds ratio [AOR] for SAVR, 2.24 [95% CI, 1.91-2.64]; AOR for SAVR with CABG, 1.96 [95% CI, 1.67-2.30]) and major morbidity or mortality (AOR for SAVR, 1.53 [95% CI, 1.39-1.69]; AOR for SAVR with CABG, 1.46 [95% CI, 1.32-1.61]) compared with the highest-volume institutions. Substantial variation in outcomes was observed across hospitals within each volume category, and prior outcomes explained a greater proportion of hospital operative outcomes than did prior volume. CONCLUSIONS: Operative outcomes after SAVR with or without CABG is inversely associated with institutional procedure volumes; however, prior outcomes are more predictive of future outcomes than is prior volume. Given the excellent outcomes observed at many lower-volume hospitals, procedural outcomes may be preferable to procedural volumes as a quality metric.