The influence and clinical significance of different pacing modes on central aortic pressure and augmentation index in non-smoking individuals / 天津医药

Objective To investigate the influence and clinical significance of single and dual-chamber pacing on central aortic pressure (CAP) and augmentation index (AI) in non-smoking individuals. Methods Totally, 83 non-smokers with pacemaker-implanted were consecutively enrolled in this study, and they were divided into three groups:dual-chamber pacemaker group (DDD, n=35), single-chamber pacemaker group (VVI, n=33) and control group (n=15). Heart rate (HR), CAP, AI, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured in three groups of patients. Finally, DDD pacing mode was turned into VVI pacing mode in patients of DDD group and the indexes were measured again. All of the indexes were recorded and analyzed. Results There were no significant changes in baseline characteristics and laboratory data between three groups (P>0.05). Left atrial diameters were significantly higher in VVI group than those of control group (P0.05). All of these indexes (CAP, AI and brachial BP) were significantly reduced after the pacing mode was changed (P<0.05). Conclusion In non-smokers, dual-chamber pacing mode can increase CAP and AI.

Study on correlation between coronary artery lesion degree with plasma brain natriuretic peptide and central aortic pressure / 重庆医学

Objective To investigate the correlation between plasma brain natriuretic peptide (BNP) ,central aortic systolic pres-sure with the degree of coronary artery lesion .Methods One hundred and fifty patients with coronary artery disease ,positive coro-nary angiographic results and without heart failure in the cardiological department of this hospital from March to June 2011 were selected and divided into the hypertension group (n=90) and the non-hypertension group(n=60) according to the blood pressure . The plasma BNP before angiography was detected by ELISA .The coronary lesion vessels and clinical scores were assessed after an-giography .The central aortic pressure before angiography was measured by the noninvasive measurement method and the diastolic blood pressure(DBP) ,systolic blood pressure(SBP) and pulse pressure(PP)were recorded .The correlation between PP and BNP was analyzed by Logistic regression .Results The plasma BNP concentration in the hypertension group was significantly higher than that in the non-hypertension group(P<0 .05) .The SBP level in 2 vessels ,3 vessels was significantly higher than that in the momal coronary group(P<0 .05) ,the PP in 3 vessels was significantly higher than that in the momal coronary group (P<0 .05) . The BNP level in 3 vessels ,2 vessels and single vessel of coronary artery lesion was significantly higher than that in the normal cor-onary artery group(P<0 .05) .The Logistic regression analysis on the PP influencing factors found that PP was closely related with the number of coronary artery lesion vessels ,lesion score ,LVEF and BNP ;the multiple correlation coefficient between PP with the number of coronary artery lesion vessels ,lesion score and BPN was 0 .91 ,its linear model was PP=0 .543 lesion vessels number +0 .656 lesion score + 0 .864 BNP .Conclusion PP of the central aortic pressure is a risk factor for the development and progress of coronary artery stenosis occurrence .BNP may be used as a plasma marker of the degree of coronary artery stenosis .

Effects of spontaneous agonal respiration on coronary perfusion pressure during untreated cardiac arrest in swine model / 中华急诊医学杂志

Objective To investigate the effects of spontaneous agonal respiration on coronary perfusion pressure (CPP) during untreated cardiac arrest (ventricular fibrillation) in swine model.Methods Ten male healthy domestic swines (25.0 ± 1.5) kg were anaesthetised,intubated and mechanically ventilated.The catheterizations were separately inserted into the right atrium and thoracic aorta to monitor aortic pressure (AOP) and right atrial pressure (RAP).A pacing electrode was inserted into the right ventricle to induce ventricular fibrillation (VF).VF was induced by intra-ventricular stimulation withalternating electric current and untreated for 8 minutes.AOP and RAP were recorded until respiratory activity ceased.The CPP before and after agonal respiration was calculated and analyzed by paired-sample T test.Results All animals presented with agonal respiration from 1 to 6 minutes after VF during the first attempt.The CPP was (7.18 ±4.22) mmHg at 1 sec before agonal respiration,(11.78 ±5.16) mmHg at 0 sec after agonal respiration,(8.75 t:4.38) mmHg at 5 sec after agonal respiration and (8.23 ± 4.55)mmHg at 6 sec after agonal respiration.The CPP at 0 sec after agonal respiration was higher than that before agonal respiration (t =-3.140,P =0.012).The CPP at 5 sec after agonal respiration was higher than that at 1 sec before agonal respiration (t =-2.828,P =0.020).There was no difference in CPP between at 6 sec after agonal respiration and at 1 sec before agonal respiration (t =-1.778,P =0.109).Conclusions Agonal respiration accompanies ventricular fibrillation.After agonal respiration,the coronary perfusion pressure is increased for 5 seconds being in favor of cardiaopulmonary resuscitation.

Central Blood Pressure and the Extent of Coronary Artery Disease / 中华高血压杂志

50%.The patients were categorized into as:one-,two-, and three-vessels coronary artery disease group.Central aortic SBP and DBP was measured by cathetarization dur- ing angiography of coronary artery and brachial blood pressure was measured using cuff method.Results Periph- eral SBP,PP and ascending aortic SBP,PP,fractional systolic pressure(FSP=SBP/MAP)were increased and as cending aortic fractional diastolic pressure(FDP=DBP/MAP)was reduced when the diseased coronary vessels were increased(P

The Relationship between Change of Cardiac Function and Systemic Oxygen Consumption according to the Dose of Dopamine in the Rabbit

PURPOSE: We'd like to know the relationship between the changes of cardiac function and systemic O2 consumption according to the increasing dose of dopamine. METHODS: Ten rabbits(from 2kg to 2.8kg) were used in this experiment. Anesthesia was induced with intraperitoneal pentobarbital sodium(35mg/kg) and tracheostomy was done. It was maintained by ventilation with a mixture of 1-3% halothane and 67-69% oxygen. Polyvinyl catheters were inserted into the femoral artery and vein and to check blood pressure and arterial blood gas analysis during the surgical procedure. Two other catheters were inserted into the internal carotid artery and external jugular vein and advanced into left ventricle and right atrium to check the pressure of each chamber, LV maximal dP/dt and to obtain blood samples of each chamber. Thoracotomy was done to expose aorta and coronary artery to check the cardiac output and coronary blood flow. We injected dopamine every 10 minutes according to the scheduled dose through external jugular vein and recorded heart rate, cardiac output, aortic pressure, maximal dP/dt, coronary blood flow by computer. Systemic O2 consumption was calculated by Fick method RESULTS: The heart rate and mean aortic pressure increased slowly according to the dose of dopamine from 20 microgram/kg/min. The cardiac otuput the maximal dP/dt and coronary blood flow was not changed until 5 microgram/kg/min, but from 7.5microgram/kg/min, it increased according to the dose of dopamine. CONCLUSION: Dopamine was a powerful inotrophic agent without increasing the systemic O2 consumption until 20microgram/kg/min, but systemic O2 consumption increased markedly at more than 20 microgram/kg/min of dopamine.

The Study of the Changes of Myocardial Histology and Left Ventricular Function according to the Total Doses of Doxorubicin in Rabbits

PURPOSE: We'd like to evaluate the relationship between the degree of cardiac damage and that of cardiac function according to the total injected dose of doxorubicin. METHODS: 12 rabbits(body weight : 2.0-3.2 kg) were used and 30 mg/m2/week of doxorubicin hydrochloride was injected intravenously. The cardiac function was checked under anesthesia, after which the thorax was opened and cardiac samples were evaluated with light and electron microscopics. RESULTS: Regardless of total injected dose of doxorubicin, there was no difference between the general appearance, sizes and thickness of both atria and ventricles of doxorubicin injected rabbits and those of normal control. The rabbits with total cumulative dose 200 mg/m2, although cardiac function is normal.