Left ventricular reverse remodelling after mitral transcatheter edge-to-edge repair: results from the EXPANDed studies.

BACKGROUND AND AIMS: Left ventricular reverse remodelling (LVRR) is a key objective of contemporary heart failure (HF) therapies and is characterized by reversal of left ventricular (LV) dilation and dysfunction.

OBJECTIVES

To report the incidence and clinical impact of early (30-day) LVRR patients with primary (PMR) and secondary mitral regurgitation (SMR) treated with mitral transcatheter edge-to-edge repair (M-TEER), and to identify independent associations with early LVRR.

METHODS

The EXPANDed cohort includes 2205 patients treated with M-TEER from the EXPAND and EXPAND G4 studies. Patients were classified as having early LVRR if they demonstrated a >10% reduction in LV dimension or volume from baseline to 30 days. All LV measurements were assessed by independent echocardiographic core laboratories.

RESULTS

Among 527 SMR patients, 338 patients (64.1%) experienced early LVRR after M-TEER. At 1 year, SMR patients with early LVRR had significantly lower rates of death or HF hospitalizations compared with those without (early LVRR: 24.7% vs no early LVRR: 35.9%, P = .009), despite similar MR reduction (MR mild or less ≥93% in both groups) and comparable improvements in functional status (NYHA ≤II ≥78%) and quality of life (∼20-points improvement per KCCQ-OS). Independent associations with early LVRR included hypertension [odds ratio (OR) = 1.96, P = .004], absence of prior cardiac surgeries (OR = 0.51, P = .002), and smaller LV end-systolic volume (OR = 0.81, P = .002).Among 536 PMR patients, 391 (73.0%) experienced early LVRR at 30 days. At 1 year, PMR patients with early LVRR group had similar clinical (composite all-cause mortality or HF hospitalization: early LVRR: 14.5% vs no early LVRR: 17.1%, P = .47) and symptomatic outcomes (≥83% NYHA ≤II; ∼19-point improvement per KCCQ-OS) compared with those without. However, among PMR patients with dilated ventricles, early LVRR group was associated with significantly lower all-cause mortality (early LVRR: 3.8%, no Early LVRR: 14.0%, P = .028).

CONCLUSIONS

Regardless of aetiology, most patients experienced early LVRR after M-TEER with significant MR reduction and symptom relief. In SMR patients, early LVRR was associated with lower rates of HF hospitalization and death.