RESUMEN
Background: Left atrial (LA) reservoir strain provides interesting information about left ventricular (LV) filling pressure. However, the advantages of atrial reservoir strain in comparison with conventional parameters in patients with myocardial infarction are not clear yet. Methods: Fifty patients with ST-elevation myocardial infarction (STEMI) prospectively underwent echocardiographic assessment of LV systolic and diastolic function by conventional parameters and two-dimensional speckle tracking longitudinal strain of left atrium. LV filling pressure was estimated by brain natriuretic peptide (BNP) levels. Results: Systolic and conventional diastolic parameters did not show significant differences between patients with increased and normal BNP values, whereas LA reservoir strain was reduced (33.1 ± 8% vs. 46.5 ± 9.8%; P = 0.001) in patients with higher BNP levels. LA reservoir strain had higher area under curve value (0.880) than the other parameters in identifying patients with elevated BNP and a cut-off value of 40.5% reached sensitivity and specificity values of 93% and 86% and positive and negative predictive values of 92% and 85%. LA reservoir strain reclassified 23 patients with increased BNP values, which were previously estimated to have normal (16 patients) and undeterminable LA pressure (seven patients) by using the recommended algorithm for diastolic function. Conclusions: LA reservoir strain is a useful tool for the evaluation of diastolic function and seems to be more sensitive than conventional parameters in the detection of subtle increase of LV filling pressure in patients with STEMI. It allows physicians to reclassify patients with undeterminable diastolic function according to conventional algorithm.
RESUMEN
BACKGROUND: Contrast-induced nephropathy (CIN) can occur after cardiovascular procedures using contrast media, which is associated with increased morbidity and mortality. RenalGuard is a closed-loop system designed to match intravenous hydration with diuretic-induced diuresis that has shown mixed results in the prevention of CIN in previous randomized controlled trials. OBJECTIVES: The STRENGTH (Study Evaluating the Use of RenalGuard to Protect Patients at High Risk of AKI) study assessed whether RenalGuard (PLC Medical Systems) is superior to standard intravenous hydration for CIN prevention in patients with chronic kidney disease undergoing complex cardiovascular procedures. METHODS: STRENGTH is a multicenter, international, open-label, postmarket, prospective, randomized (1:1) study monitored by the Cardiovascular European Research Center (Massy, France) that included a total of 259 patients with moderate to severe chronic kidney disease (estimated glomerular filtration 15-40 mL/min/m2) requiring a complex coronary, structural, or peripheral procedure with an expected contrast injection of at least 3 times the estimated glomerular filtration rate. Patients were randomized to either RenalGuard or intravenous saline hydration according to current guidelines. RESULTS: The primary endpoint, the incidence of CIN at day 3 after the procedure, was similar between the 2 groups (17/107 [15.9%] in the RG group vs 15/110 [13.9%] in the control group; P = 0.62). In addition, none of the secondary endpoints differed between the 2 groups. CONCLUSIONS: In high-risk patients undergoing complex cardiovascular interventions in experienced centers, furosemide-induced high urine output with matched hydration using the RenalGuard system did not reduce the risk of CIN and adverse outcomes at 12 months compared with conventional intravenous hydration.
