Prognostic Power of Quantitative Assessment of Functional Mitral Regurgitation and Myocardial Scar Quantification by Cardiac Magnetic Resonance.

BACKGROUND: The severity classification of functional mitral regurgitation (FMR) remains controversial despite adverse prognosis and rapidly evolving interventions. Furthermore, it is unclear if quantitative assessment with cardiac magnetic resonance can provide incremental risk stratification for patients with ischemic cardiomyopathy (ICM) or non-ICM (NICM) in terms of FMR and late gadolinium enhancement (LGE). We evaluated the impact of quantitative cardiac magnetic resonance parameters on event-free survival separately for ICM and NICM, to assess prognostic FMR thresholds and interactions with LGE quantification. METHODS: Patients (n=1414) undergoing cardiac magnetic resonance for cardiomyopathy (ejection fraction<50%) assessment from April 1, 2001 to December 31, 2017 were evaluated. The primary end point was all-cause death, heart transplant, or left ventricular assist device implantation during follow-up. Multivariable Cox analyses were conducted to determine the impact of FMR, LGE, and their interactions with event-free survival. RESULTS: There were 510 primary end points, 395/782 (50.5%) in ICM and 114/632 (18.0%) in NICM. Mitral regurgitation-fraction per 5% increase was independently associated with the primary end point, hazards ratios (95% CIs) of 1.04 (1.01-1.07; P=0.034) in ICM and 1.09 (1.02-1.16; P=0.011) in NICM. Optimal mitral regurgitation-fraction threshold for moderate and severe FMR were ≥20% and ≥35%, respectively, in both ICM and NICM, based on the prediction of the primary outcome. Similarly, optimal LGE thresholds were ≥5% in ICM and ≥2% in NICM. Mitral regurgitation-fraction×LGE emerged as a significant interaction for the primary end point in ICM (P=0.006), but not in NICM (P=0.971). CONCLUSIONS: Mitral regurgitation-fraction and LGE are key quantitative cardiac magnetic resonance biomarkers with differential associations with adverse outcomes in ICM and NICM. Optimal prognostic thresholds may provide important clinical risk prognostication and may further facilitate the ability to derive selection criteria to guide therapeutic decision-making.

Quantitative Echocardiographic Assessment and Optimal Criteria for Early Intervention in Asymptomatic Tricuspid Regurgitation.

BACKGROUND: Significant tricuspid regurgitation (TR) is associated with poor outcome and high operative mortality resulting from late presentation. Yet, the optimal timing for intervention is unknown. OBJECTIVES: The purpose of this study was to evaluate the prognostic value of echocardiographic parameters to inform early intervention in asymptomatic TR. METHODS: Using the Cleveland Clinic echocardiography database 2004 to 2018, the authors identified a consecutive cohort of asymptomatic patients with moderate to severe (3+) or severe (4+) TR. Quantitative TR and right heart parameters were retrospectively determined, and their prognostic utility for all-cause mortality was assessed. RESULTS: In 325 asymptomatic patients (mean age: 67.9 years; 79.4% female) with at least 3+ TR, there were 132 deaths (40.6%), with a median survival time of 9.9 years (95% CI: 7.9-12.7 years). By contrast, the median survival time in an age- and sex-matched cohort of symptomatic TR patients was 4.4 years (95% CI: 2.8-5.9 years). Among all the echocardiographic parameters evaluated, right ventricle free wall strain (RVFWS) and tricuspid regurgitant volume (RVol) were the strongest predictors of mortality in asymptomatic TR. The optimal discriminatory thresholds for these parameters were RVFWS <-19% and RVol >45 mL. The 5-year survival rates by number of risk factors (RF) were 93% (95% CI: 86%-96%), 65% (95% CI: 55%-74%), and 38% (95% CI: 26%-49%) for no RF, 1 RF, and both RFs, respectively. Compared with symptomatic TR, mortality was lower for asymptomatic TR with no RF (HR: 0.10; 95% CI: 0.04-0.29) or 1 RF (HR: 0.29; 95% CI: 0.14-0.58), but similar for asymptomatic TR with both RFs (HR: 1.11; 95% CI: 0.56-2.19). CONCLUSIONS: RVFWS and RVol are key prognostic markers that can be serially monitored to inform optimal timing of intervention for severe asymptomatic TR.

Be Prepared for the Unexpected: Importance of Careful Intraprocedural Transesophageal Echocardiography Assessment During MitraClip.

Transesophageal echocardiography plays a central role in the evaluation and guidance of mitral valve interventions. Our case highlights the importance of thorough intraprocedural valve evaluation using 3-dimensional and multiplanar reconstruction transesophageal echocardiography, discovering an unexpected mechanism for mitral regurgitation, to guide an alternative intervention strategy by an experienced interventional team. (Level of Difficulty: Intermediate.).