Impact of the cone operation on left ventricular size, function, and dyssynchrony in Ebstein anomaly: a cardiovascular magnetic resonance study

Abstract

BackgroundIn addition to tricuspid regurgitation (TR) and right ventricular (RV) enlargement, patients with Ebstein anomaly are at risk for left ventricular (LV) dysfunction and dyssynchrony. We studied the impact of the cone tricuspid valve reconstruction operation on LV size, function, and dyssynchrony.MethodsAll Ebstein anomaly patients who had both pre- and postoperative cardiovascular magnetic resonance (CMR) studies were retrospectively identified. From cine images, RV and LV volumes and ejection fractions (EF) were calculated, and LV circumferential and longitudinal strain were measured by feature tracking. To quantify LV dyssynchrony, temporal offsets (TOs) were computed among segmental circumferential strain versus time curves using cross-correlation analysis and patient-specific reference curves. An LV dyssynchrony index was calculated as the standard deviation of the TOs.ResultsTwenty patients (65% female) were included with a median age at cone operation of 16 years, and a median time between pre- and postoperative CMR of 2.8 years. Postoperatively, there was a decline in the TR fraction (56 ± 19% vs. 5 ± 4%, p < 0.001), RV end-diastolic volume (EDV) (242 ± 110 ml/m2 vs. 137 ± 82 ml/m2, p < 0.001), and RV stroke volume (SV) (101 ± 35 vs. 51 ± 7 ml/m2, p < 0.001). RV EF was unchanged. Conversely, there was an increase in both LV EDV (68 ± 13 vs. 85 ± 13 ml/m2, p < 0.001) and LV stroke volume (37 ± 8 vs. 48 ± 6 ml/m2, p < 0.001). There was no change in LV EF, or global circumferential and longitudinal strain but basal septal circumferential strain improved (16 ± 7% vs. 22 ± 5%, p = 0.04). LV contraction become more synchronous (dyssynchrony index: 32 ± 17 vs. 21 ± 9 msec, p = 0.02), and the extent correlated with the reduction in RV EDV and TR.ConclusionsIn patients with the Ebstein anomaly, the cone operation led to reduced TR and RV stroke volume, increased LV stroke volume, improved LV basal septal strain, and improved LV synchrony. Our data demonstrates that the detrimental effect of the RV on LV function can be mitigated by the cone operation.

SCMR Position Paper (2020) on clinical indications for cardiovascular magnetic resonance

“…In unrepaired Ebstein’s anomaly, CMR assessment of the abnormal tricuspid valve leaflets, tricuspid regurgitation, and RV volumes and function can be used to determine the suitability for operative repair [ 37 , 38 ] and predict major adverse cardiac events and atrial arrhythmia [ 39 ]. Following repair, CMR can demonstrate the extent of ventricular remodeling [ 40 , 41 ].…”

Preoperative percutaneous oxygen saturation is a predictor of postoperative adverse events after Ebstein's anomaly reconstruction

“…Cone reconstruction can reduce both tricuspid regurgitation and right ventricular end‐diastolic volume. Moreover, it can reduce right ventricular stroke volume without reducing the right ventricular ejection fraction, while left ventricular end‐diastolic volume and left ventricular stroke volume can be increased 8 . Both the short‐ and long‐term prognoses are satisfactory 7,9,10 .…”

Early and Long-Term Outcomes of Surgical Treatment of Ebstein’s Anomaly

“…Encouraging outcomes were reported by other studies performing CR [14,15] . Beroukhim et al [16] also reported improvements in RV volume and TR, besides improvement in left ventricular systolic function and synchrony in patients who underwent CR [17] .…”