Intracoronary pressure gradient measurement in acute myocardial infarction patients with the no-reflow phenomenon during primary percutaneous coronary intervention.

BACKGROUND: Various experimental and clinical studies have reported on coronary microcirculatory dysfunction ("no-reflow" phenomenon). Nevertheless, pathogenesis and effective treatment are yet to be fully elucidated. This study aimed to measure the intracoronary pressure gradient in the no-reflow artery during emergent percutaneous coronary intervention and explore the potential mechanism of no-reflow. METHODS: From September 1st, 2018 to June 30th, 2019, intracoronary pressure in acute myocardial infarction patient was continuously measured by aspiration catheter from distal to proximal segment in the Department of Coronary Care Unit, Tianjin Chest Hospital, respectively in no-reflow arteries (no-reflow group) and arteries with thrombolysis in myocardial infarction-3 flow (control group). At least 12 cardiac cycles were consecutively recorded when the catheter was pulled back. The forward systolic pressure gradient was calculated as proximal systolic pressure minus distal systolic pressure. Comparison between groups was made using the Student t test, Mann-Whitney U-test or Chi-square test, as appropriate. RESULTS: Intracoronary pressure in 33 no-reflow group and 26 in control group were measured. The intracoronary forward systolic pressure gradient was -1.3 (-4.8, 0.7) and 3.8 (0.8, 8.8) mmHg in no-reflow group and control group (Z = -3.989, P < 0.001), respectively, while the forward diastolic pressure gradient was -1.0 (-3.2, 0) and 4.6 (0, 16.5) mmHg in respective groups (Z = -3.851, P < 0.001). Moreover, the intracoronary forward pressure gradient showed significant difference between that before and after nicorandil medication (Z = -3.668, P < 0.001 in systolic pressure gradient and Z = -3.530, P < 0.001 in diastolic pressure gradient). CONCLUSIONS: No reflow during emergent coronary revascularization is significantly associated with local hemodynamic abnormalities in the coronary arteries. Intracoronary nicorandil administration at the distal segment of a coronary artery with an aspiration catheter could improve the microcirculatory dysfunction and resume normal coronary pressure gradient. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov (No. NCT03600259).

High uric acid level predicts left atrial thrombus or spontaneous echo contrast detected by transesophageal echocardiography: Meta-analysis and systematic review.

BACKGROUND: Recent observational studies have suggested that the patients with hyperuricemia have a higher risk of having left atrial thrombus (LATH) or left atrial spontaneous echo contrast (LASEC) by transesophageal echocardiography (TEE), while the ultimate predictive value of a high uric acid (UA) level on LATH/LASEC remained obscure. METHODS: We searched the PubMed and Cochrane clinical trials databases up to July 2015. Following screening the 369 initially identified studies, we analyzed six observational studies with 2381 patients. RESULTS: The meta-analysis of these studies showed that an elevated serum UA level was associated with a higher likelihood of LATH/LASEC (OR = 1.59, 95%CI 1.13-2.23, P = 0.008), while significant differences exist among individual trials (P < 0.00001 and I2 = 85%). Sensitivity analysis failed to find any heterogeneity. CONCLUSION: An elevated UA level was associated with a higher risk of detecting a left atrial abnormality represented by LATH/LASEC.

High Killips Class as a Predictor of New-onset Atrial Fibrillation Following Acute Myocardial Infarction: Systematic Review and Meta-analysis.

BACKGROUND: Recent observational studies have shown that patients with higher Killips score (>I) have higher risk of new-onset atrial fibrillation (NOAF) following acute myocardial infarction (AMI), while others drew a neutral conclusion. The ultimate predictive value of high Killips class on NOAF remained obscure. METHODS: PubMed, Web of Science, China National Knowledge Infrastructure, and the Cochrane Controlled Trials Register Databases were searched until February 2015. Of the 3732 initially identified studies, 5 observational studies with 10,053 patients were analyzed. RESULTS: The meta-analysis of these studies showed that higher Killips score on admission was associated with higher incidence of NOAF following AMI (odds ratio = 2.29, 95% confidence interval 1.96-2.67, P < 0.00001), while no significant differences exist among individual trials (P = 0.14 and I2 = 43%). CONCLUSIONS: Killips class >I was associated with the higher opportunity of developing NOAF following AMI.