Speckle Tracking Echocardiographic Assessment of Left Ventricular Function by Myocardial Strain Before and After Aortic Valve Replacement

BACKGROUND & OBJECTIVES: In patients of aortic stenosis and regurgitation, pressure and volume effects on left ventricular function are occult and missed by routine echocardiography markers like ejection fraction (EF). Speckle tracking analysis by measuring global longitudinal strain and global circumferential strain seems to ascertain this occult LV function parameters at an early phase in a more comprehensive manner. Limited studies have examined these parameters pre/post aortic valve replacement (AVR). METHODS: 94 consecutive patients with symptomatic severe aortic stenosis (AS) or aortic regurgitation (AR), planned for AVR were included (as per set inclusion criteria) along with 15 normal controls-15 months prospective study. Routine echocardiography and speckle tracking imaging was done at baseline (pre AVR) and post AVR at 1st week, 1st month and 3rd month of follow up. RESULTS: 90 patients completed study (70 in AS and 20 in AR group). In AS group mean values (± 2 standard deviations) of global longitudinal strain (GLS) improved from a baseline −10.9% (± 3.9) to −19.4% (±3.8) at 3rd month (p value < 0.0001). Mean values of global circumferential strain (GCS) too improved from −17.3% (±4.5) to −21.4% (±3.6) respectively (p value < 0.0001). In AR group too mean values of global longitudinal strain progressed from a baseline −12.6% (±3.9) to −19.4% (±3.4) at three months of follow (p value < 0.0001) and mean values of global circumferential strain also progressed from −15.3% (±3.4) at baseline to −21.7% (±3.1) respectively (p value < 0.0001). CONCLUSION: Magnitude of recovery of GLS and GCS after AVR was more as compared to recovery in EF. Poor GLS/GCS values at baseline were associated with lesser recovery pressing need for an earlier intervention.