Background: Cardiogenic shock (CS) remains the leading cause of death in acute MI (AMI), and precise risk stratification is crucial for the subsequent immediate management of CS. However, effective early risk-stratification tools for patients with CS are lacking.
Hypothesis: In this study, we hypothesised that risk stratification based on left ventricular (LV) global longitudinal strain (GLS) is a better predictor of early outcome in patients with CS complicating AMI.
Methods: The LV GLS was estimated by a speckle-tracking-derived algorithm. The 30-day mortality was chosen for the indicator of early outcome after primary percutaneous coronary intervention in patients with CS complicating AMI. The possible predictors of outcome were chosen from demographic, clinical, cardiac enzyme, angiographic and echocardiographic measurements by univariable hazard regression. Independent relationships of possible predictors were confirmed by multivariable hazard regression.
Results: A total of 51 patients with CS complicating AMI were selected (mean age 64 ± 14 years, 76% men). The 30-day mortality was 27.5% (n=14). LV GLS was significantly impaired in patients who died compared with survivors (−8.4 ± 3.9% versus −13.1 ± 4.4%, p<0.001). The QRS time (HR 1.02, 95% CI [1.00–1.04], p<0.05), peak troponin level (HR 1.01, 95% CI [1.00–1.01], p<0.01), estimated glomerular filtration rate (HR 0.97, 95% CI [0.95–0.99], p<0.01), E/e’ ratio (HR 1.06, 95% CI [1.02–1.09], p<0.001) and LV GLS (HR 1.19, 95% CI [1.07–1.33], p<0.001) were possible predictors of early outcome by univariable hazard regression. After adjustment for the above-mentioned variables, LV GLS was the only variable which was found to be an independent predictor of early outcome (HR 1.22, 95% CI [1.07–1.40], p=0.004). Furthermore, LV GLS showed good predictive capacity in receiver-operating characteristic curve analysis (area under the curve 0.79, cut-off value −10.8%, 95% CI [0.66–0.92], p<0.01). Kaplan–Meier estimation showed that patients with good LV recovery (LV GLS <−10.8%) had improved survival (log-rank p=0.006).
Conclusion: The risk stratification based on LV GLS is a better predictor of early outcome in patients with CS complicating AMI.