Evaluation on the impact of spontaneous reperfusion on cardiac muscle of acute myocardial infarction by three-dimensional speckle tracking imaging.

OBJECTIVE: To explore the effect of spontaneous reperfusion (SR) on three-dimensional myocardial strain in patients with acute anterior myocardial infarction by three-dimensional speckle tracking imaging (3D-STI) technology. PATIENTS AND METHODS: Patients diagnosed with acute anterior myocardial infarction during 2013 to 2016 were consecutively selected and divided into SR group and non-spontaneous reperfusion (Non-SR) group based on whether there was SR. Patients in both groups received direct percutaneous coronary intervention (PCI) in time window. Baseline information, patency rates of culprit vessel, durations of operation, intraoperative non-reflow phenomenon ratios, and thrombolysis in myocardial infarction (TIMI) blood flows after reperfusion of patients in each group were recorded. Hospital stays of patients were compared between the two groups. Before discharge, left ventricular ejection fraction (LVEF) and left ventricular end-diastolic diameter (LVEDd) were measured. Global longitudinal strain (GLS), global radial strain (GRS), and global circumferential strain (GCS) of left ventricular (LV) were also detected by 3D-STI, so as to assess movement situations of ventricular wall and cardiac muscle in occlusive blood vessel distribution area. LVEF, LVEDd and various 3D-STI parameters were reexamined and compared one year after discharge. RESULTS: There were no significant differences between the Non-SR group and the SR group regarding the patency rate of culprit vessel, duration of operation, intraoperative non-reflow phenomenon ratio, TIMI blood flow after reperfusion, and LVEDd (p>0.05). Both LVEF before discharge and LV three-dimensional strain indexes of the SR group, were clearly higher than those of the Non-SR group (p<0.05). After one-year follow-up, the SR group had a remarkably lower LVEDd than the Non-SR group (p<0.05). LVEF of the SR group was overtly higher than that of the Non-SR group (p<0.05). LV three-dimensional strain indexes were also distinctly higher in the SR group than in the Non-SR group (p<0.05). There were good correlations between GLS, GRS, GCS and LVEF (r values were -0.620, -0.674 and 0.723, respectively). CONCLUSIONS: SR can improve nosocomial and long-term LV remodeling in patients with acute anterior myocardial infarction, and 3D-STI is able to assess ventricular remodeling after myocardial infarction.

Massive pulmonary air embolism during the implantation of pacemaker, case reports and literature analysis.

OBJECTIVES: Pacemaker implantation has developed into a mature technology, meanwhile, implantable cardioverter-defibrillators (ICD) and cardiac resynchronization therapy (CRT), as extended pace making technology, are both carried out in rising frequency. Massive pulmonary air embolism is a rare but fatal complication accompanying with such pace making process. The objective of this study was to investigate the epidemiology, pathophysiological mechanism, occurrence and treatment for this kind of complication. PATIENTS AND METHODS: Two cases of complicated massive pulmonary gas embolism were presented: one in CRT and the other in pacemaker implantation, both of which were captured rapidly and treated successfully by inhalation of high flow oxygen, closure of gas inflow tract, position change, and vasoactive drugs. Moreover, published literatures about air embolism in the process of pacemaker implantation or CRT/ICD were summarized and analyzed. RESULTS: Complicated massive pulmonary air embolisms could be successfully resolved with satisfied short-term prognosis. Literature analysis showed that massive pulmonary air embolism is very rare in the course of pacemaker implantation, and coughing or deep breathing, advanced age, preoperative sedation, sheath with large cavity, improperly operating the hemostasis valve and diminished compliance of pulmonary circulation might be risk factors for air embolism. CONCLUSIONS: Massive pulmonary air embolism during pace making which is very rare in the course of pacemaker implantation is one kind of life-threatening complication. Rapid judgment and timely treatment can avoid a catastrophic event, which could prevent adverse impact on the short-term prognosis, while further observation is required to explore the long-term prognosis.