OBJECTIVETo evaluate the beneficial effects of adenosine on myocardial no-reflow in a mini-swine model of acute myocardial infarction (AMI) and reperfusion.

METHODSTwenty-four animals were randomly assigned to 3 groups: 8 in controls, 8 in adenosine-treated and 8 in sham-operated. The groups were subjected to 3 hours of coronary occlusion followed by 60 minutes of reperfusion except the sham-operated group. Data on hemodynamics and coronary blood flow volume (CBV) were collected. The area of no-reflow was evaluated by both myocardial contrast echocardiography (MCE) in vivo and histopathological means and necrosis area was measured with triphenyltetrazolium chloride staining.

RESULTS(1) In control group, systolic and diastolic blood pressure (SBP and DBP), left ventricular systolic pressure, maximal rate of increase and decline in left ventricular pressure (+/- dp/dtmax) and cardiac output significantly declined (P < 0.05-0.01), while left ventricular end-diastolic pressure (LVEDP) and pulmonary capillary wedge pressure (PCWP) significantly increased at the end of 3 hours of LAD occlusion (both P < 0.01), with +/- dp/dtmax further significantly declined (both P < 0.05) at 60 minutes of reperfusion. In adenosine treated group, the changes of SBP and DBP, left ventricular systolic pressure, +/- dp/dtmax, cardiac output, LVEDP and PCWP were the same as those in the control group after AMI and reperfusion, while left ventricular systolic pressure, +/- dp/dtmax, cardiac output, LVEDP and PCWP recovered significantly at 60 minutes of reperfusion compared with those at 6 hours AMI. (2) In control group, the coronary ligation areas (LA) were similar (P > 0.05) detected by MCE in vivo and histopathological evaluation, and the areas of no-reflow were both as high as 67.5% and 69.3%, respectively. The final necrosis area reached 99% of LA. Compared with those in the control group, there was no significant difference in LA on both MCE and histopathological evaluation in the adenosine-treated group, though the areas of no-reflow on both methods were significantly decreased to 21% and 22% (both P < 0.01) and final necrosis area was also significantly decreased to 75% of LA (P < 0.05). (3) In the control group, CBV were significantly declined to 45.8% and 50.6% of the baseline at immediately after release of 3 hours occlusion and at 60 minutes of reperfusion, respectively (both P < 0.01). In the adenosine-treated group, CBV were also significantly declined at immediately after release of 3 hours occlusion, and at 60 minutes of reperfusion (both P < 0.05), though significantly increased to 79.5% and 79.9% of the baseline which were both significantly higher than those in the control group.

CONCLUSIONAdenosine has an effective role in preventing myocardial no-reflow, improving left ventricular function and reducing infarct area during AMI and reperfusion in mini-swine.

Adenosine ; pharmacology ; therapeutic use ; Animals ; Cardiac Output ; drug effects ; Coronary Circulation ; drug effects ; Disease Models, Animal ; Female ; Male ; Myocardial Infarction ; drug therapy ; physiopathology ; Myocardial Reperfusion Injury ; prevention & control ; Pulmonary Wedge Pressure ; drug effects ; Swine ; Swine, Miniature

The effects of electroacupuncture (EA) on the minimum alveolar concentration (MAC) and on the cardiovascular system were evaluated with dogs under isoflurane anesthesia. Eight healthy male beagles were randomly assigned to six study groups (five heads/group) with washout intervals of 7 ~ 31 days between experiments for recovery and anesthetic clearance. MAC of isoflurane and cardiovascular parameters were determined after EA at nonacupoint and and at acupoints LI-4, SP-6, ST-36 and TH-8. Electroacupuncture for 30 minutes at LI-4, SP-6, ST-36 and TH-8 acupoints lowered the MAC of isoflurane by 17.5 +/- 3.1%, 21.3 +/- 8.0%, 20.5 +/- 8.2% and 15.6 +/- 3.1%, respectively (p < 0.05). However, electrical stimulation of nonacupoint did not induce a significant change in MAC of isoflurane. In the cardiovascular system, the ST-36 group did not induce any significant change in cardiovascular parameters. In the TH-8 group, the mean and diastolic arterial pressure and the systemic vascular resistance were decreased. In the LI-4 group, cardiac output and cardiac index decreased after EA. These results indicate that EA at LI-4, SP-6 and ST-36 have advantages in isoflurane anesthesia in terms of reducing the dose of anesthetics and minimizing cardiovascular side effects.
Anesthesia, Inhalation/adverse effects/*veterinary ; Anesthetics, Inhalation/*pharmacokinetics/pharmacology ; Animals ; Blood Pressure/drug effects ; Cardiac Output ; Dogs/*metabolism/physiology ; Electroacupuncture/*veterinary ; Heart Rate/drug effects ; Isoflurane/*pharmacokinetics/pharmacology ; Male ; Pulmonary Alveoli/*metabolism ; Pulmonary Wedge Pressure/drug effects ; Random Allocation ; Vascular Resistance/drug effects

OBJECTIVEAs an important method of hemodynamic assessment in idiopathic pulmonary arterial hypertension (IPAH), cardiac catheterization combined with pulmonary vasoreactivity testing remains with limited experience in children, and the acute pulmonary vasodilator agents as well as response criteria for vasoreactivity testing remain controversial. The aim of this study was to investigate the clinical importance, agent selection, and responder definition of cardiac catheterization combined with pulmonary vasoreactivity testing in pediatric IPAH.

METHODThe patients admitted to Department of Pediatric Cardiology of Beijing Anzhen Hospital between April 2009 and September 2013 with suspected IPAH, under 18 years of age, with WHO functional class II or III, were enrolled. All the patients were arranged to receive left and right heart catheterization and pulmonary vasoreactivity testing with inhalation of pure oxygen and iloprost (PGI2) respectively. Hemodynamic changes were analyzed, and two criteria, the European Society of Cardiology recommendation criteria (Sitbon criteria) and traditional application criteria (Barst criteria), were used to evaluate the test results.

RESULTThirty-nine cases of children with suspected IPAH underwent cardiac catheterization. In 4 patients IPAH was excluded; 4 patients developed pulmonary hypertension crisis. The other 31 patients received standard cardiac catheterization and pulmonary vasoreactivity testing. Baseline mean pulmonary artery pressure (mPAP) was (66 ± 16) mmHg (1 mmHg = 0.133 kPa), and pulmonary vascular resistance index (PVRI) (17 ± 8) Wood U · m². After inhalation of pure oxygen, mPAP fell to (59 ± 16) mmHg, and PVRI to (14 ± 8) Wood U · m² (t = 4.88 and 4.56, both P < 0.001) . After inhalation of PGI2, mPAP fell to (49 ± 21) mmHg, and PVRI to (12 ± 9) Wood U · m² (t = 7.04 and 6.33, both P < 0.001). According to the Sitbon criteria, the proportion of pure oxygen responders was 6.5% (3/31) , while PGI2 responders was 35.5%, and the difference was significant (P = 0.004). According to the Barst criteria, the proportion of pure oxygen responders was 16.1% (5/31), while PGI2 responders was 51.6% (16/31), and the difference was significant (χ² = 0.09, P = 0.001).

CONCLUSIONFor children with IPAH, cardiac catheterization combined with pulmonary vasoreactivity testing has important value in differential diagnosis, severity estimation, and treatment (including the emergency treatment) choices. Pulmonary hypertension crisis is an important complication of cardiac catheterization in pediatric IPAH. Younger age, general anesthesia, crisis history, and poor heart function are important risk factors for pulmonary hypertension crisis. PGI2 is a relatively ideal agent for vasoreactivity testing in children with IPAH, which has more responders than traditionally used pure oxygen.

RESULTSof responders are not completely consistent using different criteria, and comprehensive evaluation should be done according to the goals of treatment in clinical practice.

Administration, Inhalation ; Adolescent ; Anesthesia, General ; Cardiac Catheterization ; Child ; Child, Preschool ; Familial Primary Pulmonary Hypertension ; diagnosis ; physiopathology ; Female ; Hemodynamics ; Humans ; Iloprost ; administration & dosage ; Infant ; Male ; Pulmonary Artery ; physiopathology ; Pulmonary Circulation ; drug effects ; Pulmonary Wedge Pressure ; drug effects ; Severity of Illness Index ; Vascular Resistance ; drug effects ; Vasodilator Agents ; administration & dosage