| Objective:With conventional echocardiography and Two-dimensional SPeckle Tracking Imaging(2D-STI),patients with bradyarrhythmia(BA)were evaluated 3 months after permanent dual pacemaker implantation.Compared with changes in left atrial and left ventricular functions before implantation and left atrial stress,the short-term influence of implantation of double-chamber permanent pacemaker on left atrial function in patients with bradycardia was studied,and the diagnosis of early changes in left atrial function by two ultrasound techniques was compared,providing a new evaluation method and reference for postoperative monitoring and treatment of cardiac function in patients with bradycardia.Methods:A total of 30 patients,including 14 males and 16 females,who were admitted to the Department of Cardiology,the First Affiliated Hospital of Gannan Medical University from January 2021 to December 2022 and who were confirmed by24-hour holter electrocardiogram after admission to receive chronic arrhythmias(including sick sinoatrial syndrome and atrioventricular block)and proposed to receive dual chamber permanent pacemaker implantation were included.Twelve patients with sick sinus syndrome and 18 patients with atrioventricular block were aged 37-70 years with an average age of(57.07±9.84)years.General parameters and echocardiographic parameters of subjects before and 3 months after surgery were collected to ensure that each subject was in sinus rhythm for systematic routine echocardiographic examination.General parameters include patient age,gender,height,weight,heart rate,blood pressure,calculated Body Surface Area,BSA)[BSA(m~2)=0.0061×height(cm)+0.0128×weight(kg)-0.1529],Body Mass Index(BMI)[BMI(kg/m~2)=weight(kg)/height ~2(m~2)].Echocardiographic parameters include:(1)Two-dimensional ultrasonic parameters:Left Ventricular Ejection Fraction(LVEF),Left Atrial Volume(LAV),in which Left Atrial Volume includes maximum(Left Atrial Volume max,LAVmax),Left Atrial Volume min(LAVmin)and Left Atrial presystolic Volume(LAVp).Computed Left Atrial Volume Index(LAVI)[Left Atrial volume index(LAVI)=left atrial volume(ml)/body surface area(m~2)],and calculated left atrial Emptying Fractions(Active Left Atrial Emptying Fractions,LAAEF)[LAAEF=LAVp-LAVmin)/LAVp×100%]and Left Atrial Emptying Fractions(TotalLeftAtrialEmptyingFractions,LATEF)[LATEF=(LAVmax-LAVmin)/LAVmax×100%].(2)Doppler ultrasonic parameters:The peak value of early diastolic blood flow velocity(peak E)and late diastolic blood flow velocity(peak A)were measured at the four-chamber view of the apex of the heart,and E/A was calculated.Then tissue Doppler mode was selected to measure the peak value of systolic,early diastolic and late diastolic velocity(A’)at the mitral ring level.And calculate E/e’,e’/a’.(3)Parameters of two-dimensional spot tracking echocardiography:The Left Atrial Positive Strain(LAPS)and the first Negative peak Strain(LANS)in the Left Atrial strain curve were measured as defined by LAPS to reflect the left atrial channel function.LANS reflects the active systolic function of the left atrium,and the sum of their absolute values is the storage function of the left atrium.SPSS 28.0 software was used for statistical analysis.Measurement data with"mean+/-standard deviation"((?)±s)said,preoperative and postoperative group of measurement data compared with paired t test.All statistical results were statistically significant with P<0.05.To analyze the short-term effects of double-chamber permanent pacemaker on left atrial function in patients with bradycardia and compare the diagnosis of early changes in left atrial function by two ultrasound techniques,so as to provide a new evaluation method and reference for postoperative monitoring and treatment of cardiac function in patients with bradycardia.Results:1.Three months after pacemaker implantation,the heart rate of the patient increased compared with that before surgery[(68.21±8.80)bpm vs.(56.86±17.78)bpm,P<0.05],the difference was statistically significant(P<0.05).2.Compared with the preoperative results,the left ventricular ejection fraction(LVEF)of the patients had no significant change in 3 months after operation[(62.21±2.96)%vs.(61.50±3.76)%,(P>0.05)],and the difference was not statistically significant(P>0.05).3.3 months after surgery,Left atrial maximum volume(LAVmax)[(42.28±2.65)ml to(42.61±2.96)ml],left atrial minimum volume(LAVmin)[(16.07±1.93)ml to(16.14±1.88)ml],left atrial pre-systolic volume(LAVp)[(25.36±1.82)ml ratio(25.96±1.778)ml],left atrial volume index(LAVI)[(27.38±2.45)(ml/m2)ratio(26.55±1.46)(ml/m2)],left atrial active empty fraction(LAAEF)There were no significant changes in the ratio of(37.22±14.54)%to(38.87±9.84)%and left atrial total empty fraction(LATEF)[(61.88±5.34)%to(62.28±3.81)%]compared with the preoperative results(P>0.05).4.Left ventricular diastolic function parameters of the patient:Peak mitral orifice blood flow velocity in early diastolic period(peak E)[(91.41±12.40)cm/s ratio(92.79±13.34)cm/s],peak blood flow velocity in late diastolic period(peak A)[(78.44±10.67)]There was no significant difference between the ratio of cm/s(77.62±10.01)cm/s and E/A[ratio of(1.17±0.12)to(1.20±0.14)]at 3 months after operation and before operation(P>0.05).The early diastolic velocity peak(e’)[(9.26±0.84)cm/s vs(9.78±1.07)cm/s]and late diastolic velocity peak(a’)[(7.54±1.14)cm/s vs(7.92±1.30)cm/s]at mitral ring level were lower than those before surgery.The difference was statistically significant(P<0.05).There was no significant difference between E/e’[(9.90±1.19)ratio(9.49±0.89)]and e’/a’[(1.17±0.17)ratio(1.20±0.26)]at 3 months after operation and before operation(P>0.05).5.3 months postoperatively,patients with left atrial strain curve of the first negative peak strain(LANS)absolute value decreases,positive peak strain(LAPS)and the sum of the absolute value(LAPS+|LANS|)compared with preoperative is reduced,the difference was statistically significant(P<0.05).Conclusion:1.Dual chamber pacemaker implantation can increase the heart rate of patients with bradycardia and avoid cardiac arrest.2.For patients with bradycardia with ejection fraction retention(LVEF>50%),the left ventricular systolic function of patients with dual-chamber pacemaker is not significantly affected in the short term after implantation.3.Patients’left ventricular diastolic function tends to decrease in the short term after dual chamber pacemaker implantation.4.In the short term after the implantation of the double-chamber pacemaker,the left atrial storage function,channel function and pump function of the patient are reduced due to the influence of the pacemaker.Compared with conventional echocardiography,two-dimensional spot tracking can detect the early injury of atrial function earlier and more accurately,providing more accurate reference basis and a new evaluation method for the clinic. |
PDF Full Text Request