Degenerative Mitral Regurgitation Outcomes in Asian Compared With European-American Institutions.

Background: Clinical outcome and interventional thresholds for degenerative mitral regurgitation (DMR) were developed in studies of patients at European and American institutions (EAIs), but little is known about patients at Asian institutions (AsIs). Objectives: This study sought to contrast DMR presentation/management/outcomes of AsI patients vs EAI patients. Methods: Patients with DMR due to flail leaflet from Hong Kong and Singapore (AsI cohort, n = 737) were compared with EAI patients (n = 682) enrolled in the MIDA (Mitral regurgitation International Database) registry with similar eligibility criteria. Results: AsI patients presented similar DMR lesion/consequences vs EAI patients, but they were younger, with fewer symptoms (74% vs 44% Class I), more sinus rhythm (83% vs 69%), and lower EuroSCORE II (European System for Cardiac Operative Risk Evaluation II) (0.9 ± 0.5 vs 1.4 ± 1.5; all P < 0.0001). Imaging showed smaller absolute left atrial/ventricular dimensions in AsI patients, belying cardiac dilatation with larger body surface area-indexed diameters (all P < 0.01). Surgical/interventional mitral repair was similarly predominant (90% vs 91%; P = 0.47), and early repair was similarly beneficial (for AsI patients, adjusted HR: 0.28; 95% CI: 0.16-0.49; for EAI patients, HR: 0.32; 95% CI: 0.20-0.49; both P < 0.0001). However, AsI patients underwent fewer interventions (55% ± 2% vs 77% ± 2% at 1 year; P < 0.0001) and incurred excess mortality (adjusted HR: 1.60 [95% CI: 1.13-2.27] vs EAI patients; P = 0.008) at long-term postdiagnosis. Propensity score matching (434 patient pairs), which balanced all clinical characteristics, confirmed that there was undertreatment and excess mortality in the long term in AsI patients with DMR (P < 0.0001). Conclusions: Imaging may underestimate volume overload in AsI patients due to smaller cardiac cavities related to smaller body size compared with EAI patients with similar mitral lesions and DMR severity. AsI patients enjoy similar mitral repair predominance and early intervention benefits but undergo fewer mitral interventions than EAI patients and incur subsequent excess mortality, suggesting the need to account for imaging and cultural specificity to improve DMR outcomes worldwide.

Survival loss linked to guideline-based indications for degenerative mitral regurgitation surgery.

AIMS: Operating on patients with severe degenerative mitral regurgitation (DMR) is based on ACC/AHA or ESC/EACTS-guidelines. Doubts persist on best surgical indications and their potential association with postoperative survival loss. We sought to investigate whether guideline-based indications lead to late postoperative survival loss in DMR-patients. METHODS AND RESULTS: : We analyzed outcome of 2833 patients from the MIDA-registry undergoing surgical correction of DMR. Patients were stratified by surgical indications: Class-I-trigger (symptoms, left ventricular end-systolic diameter≥40mm, or left ventricular ejection fraction<60%, n=1677), isolated-Class-IIa-trigger (atrial fibrillation [AF], pulmonary hypertension [PH], or left atrial diameter≥55mm, n=568), or no-trigger (n=588). Postoperative survival was compared after matching for clinical differences. Restricted-mean-survival time (RMST) was analyzed. During a median 8.5-year follow-up, 603 deaths occurred. Long-term postoperative survival was lower with Class-I-trigger than in Class-IIa-trigger and no-trigger (71.4±1.9%, 84.3±2.3%, 88.9±1.9% at 10 years, p<0.001). Having at least one Class-I-criterion led to excess mortality (p<0.001), while several Class-I-criteria conferred additional death-risk (HR:1.53, 95%CI:1.42-1.66). Isolated-Class-IIa-triggers conferred an excess mortality risk versus those without (HR:1.46, 95%CI:1.00-2.13, p=0.05). Among these patients, isolated-PH led to decreased postoperative-survival versus those without (83.7%±2.8% vs. 89.3%±1.6%, p=0.011), with the same pattern observed for AF (81.8%±5.0% vs. 88.3%±1.5%, p=0.023). According to RMST-analysis, compare to those operated on without triggers, operating on Class-I-trigger patients led to 9.4-month survival-loss (p<0.001) and operating on isolated-Class-IIa-trigger patients displayed 4.9-month survival loss (p=0.001) after 10-years. CONCLUSIONS: : Waiting for the onset of Class-I or isolated-Class-IIa-triggers before operating on DMR patients is associated with postoperative survival loss. These data encourage an early surgical-strategy.

Direct 3D ultrasound fusion for transesophageal echocardiography.

BACKGROUND: Real-time three-dimensional transesophageal echocardiography (3D TEE) has been increasingly used in clinic for fast 3D analysis of cardiac anatomy and function. However, 3D TEE still suffers from the limited field of view (FoV). It is challenging to adopt conventional multi-view fusion methods to 3D TEE images because feature-based registration methods tend to fail in the ultrasound scenario, and conventional intensity-based methods have poor convergence properties and require an iterative coarse-to-fine strategy. METHODS: A novel multi-view registration and fusion method is proposed to enlarge the FoV of 3D TEE images efficiently. A direct method is proposed to solve the registration problem in the Lie algebra space. Fast implementation is realized by searching voxels on three orthogonal planes between two volumes. Besides, a weighted-average 3D fusion method is proposed to fuse the aligned images seamlessly. For a sequence of 3D TEE images, they are fused incrementally. RESULTS: Qualitative and quantitative results of in-vivo experiments indicate that the proposed registration algorithm outperforms a state-of-the-art PCA-based registration method in terms of accuracy and efficiency. Image registration and fusion performed on 76 in-vivo 3D TEE volumes from nine patients show apparent enlargement of FoV (enlarged around two times) in the obtained fused images. CONCLUSIONS: The proposed methods can fuse 3D TEE images efficiently and accurately so that the whole Region of Interest (ROI) can be seen in a single frame. This research shows good potential to assist clinical diagnosis, preoperative planning, and future intraoperative guidance with 3D TEE.

Valvular Disease and Heart Failure with Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome of shortness of breath and/or exercise intolerance secondary to elevated left ventricular filling pressures at rest or with exertion either as a result of primary diastolic dysfunction (primary HFpEF) or secondary to specific underlying causes (secondary HFpEF). In secondary HFpEF, early intervention of underlying valvular heart disease generally improves symptoms and prolongs survival. In primary HFpEF, there is increasing awareness of the existence and prognostic implications of secondary atrioventricular valve regurgitation. Further studies will clarify their mechanisms and the effectiveness of valvular intervention in this intriguing HFpEF subgroup.