Improvement In Heart Rate Research Articles

Cardioprotective actions of two bioflavonoids, quercetin and rutin, in experimental myocardial infarction in both normal and streptozotocin-induced type I diabetic rats

Abstract Objectives Revascularization therapy is the mainstay of treatment in the management of myocardial infarction in normal and diabetic patients. We attempted to evaluate the cardioprotective actions of quercetin and rutin in ischaemia-reperfusion-induced myocardial infarction in both normal and diabetic rats. Methods Myocardial infarct size was measured using the staining agent 2,3,5-triphenyltetrazoliumchloride. Serum and tissue malondialdehyde levels and superoxide dismutase and catalase in heart tissue were estimated spectrophotometrically. A lead II electrocardiogram was monitored at various intervals throughout the experiment. Key findings Results demonstrated the larger infarct size, enhanced lipid peroxidation, partial depletion of antioxidant enzymes and drastic drop in heart rate in diabetic hearts subjected to in-vivo ischaemia-reperfusion in comparison to normal rats subjected to ischaemia-reperfusion. Furthermore, quercetin and rutin significantly limit the infarct size in both normal and diabetic animals in a similar fashion. However, rutin offered complete cardioprotection at a dose of 10 mg/kg in terms of limiting infarct size. Both flavonoids could partially but significantly attenuate the lipid peroxidation. In addition, treatment has shown moderate improvement in heart rate in both normal and diabetic rats. Conclusions Our data suggest the possible cardioprotective effects of quercetin and rutin in ischaemia-reperfusion injury in both normal and diabetic rats, and that protection might be in part due to the attenuation of oxidative stress and moderate increment in antioxidant reserves.

Cardioprotective actions of two bioflavonoids, quercetin and rutin, in experimental myocardial infarction in both normal and streptozotocin-induced type I diabetic rats

Revascularization therapy is the mainstay of treatment in the management of myocardial infarction in normal and diabetic patients. We attempted to evaluate the cardioprotective actions of quercetin and rutin in ischaemia-reperfusion-induced myocardial infarction in both normal and diabetic rats. Myocardial infarct size was measured using the staining agent 2,3,5-triphenyltetrazoliumchloride. Serum and tissue malondialdehyde levels and superoxide dismutase and catalase in heart tissue were estimated spectrophotometrically. A lead II electrocardiogram was monitored at various intervals throughout the experiment. Results demonstrated the larger infarct size, enhanced lipid peroxidation, partial depletion of antioxidant enzymes and drastic drop in heart rate in diabetic hearts subjected to in-vivo ischaemia-reperfusion in comparison to normal rats subjected to ischaemia-reperfusion. Furthermore, quercetin and rutin significantly limit the infarct size in both normal and diabetic animals in a similar fashion. However, rutin offered complete cardioprotection at a dose of 10 mg/kg in terms of limiting infarct size. Both flavonoids could partially but significantly attenuate the lipid peroxidation. In addition, treatment has shown moderate improvement in heart rate in both normal and diabetic rats. Our data suggest the possible cardioprotective effects of quercetin and rutin in ischaemia-reperfusion injury in both normal and diabetic rats, and that protection might be in part due to the attenuation of oxidative stress and moderate increment in antioxidant reserves.

Impact of early and standardized treatment with amiodarone on therapeutic success and outcome in pediatric patients with postoperative tachyarrhythmia

Effects of timing of inception of amiodarone antiarrhythmic treatment after corrective surgery for congenital heart defects are not yet well defined. In a 10-year prospective observational study, 71 of 2651 patients (2885 procedures, 2106 bypass procedures) received amiodarone for newly detected postoperative atrial (n = 70) or ventricular (n = 7) tachyarrhythmia: early treatment (initiation within 60 minutes of arrhythmia detection) and late treatment (after that). From an interim analysis, a treatment protocol was established (32 patients). Inotropic requirements were monitored, as were heart rate, blood pressure, central venous pressure, and sedation requirements. With early treatment (n = 29), delay before start of amiodarone was 40.7 +/- 21.9 minutes, versus 227.7 +/- 228.1 minutes (P < .001) with late treatment (n = 42). There were significant benefits of early treatment for times to rate (155.9 +/- 299.8 vs 407.6 +/- 376.9 minutes, (P < .001) and rhythm control (400.4 +/- 845 vs 1038.5 +/- 1158.4 minutes, P < .001), reduction in dose needed for rate control (28.2 +/- 45.2 vs 66.5 +/- 137.5 mg, P < .025), and significant reduction in pediatric cardiac intensive care unit stay (3.32 +/- 1.9 vs 5.26 +/- 4.27 days, P < .01). There were continuous improvements in heart rate, blood pressure, and filling pressures without additional inotropic requirements or side effects. Early treatment of postoperative tachyarrhythmia with amiodarone according to a standardized treatment protocol is safe and has beneficial effects on arrhythmia control and pediatric cardiac intensive care unit stay.

THE IMPACT OF NONINVASIVE VENTILATION DURING THE PHYSICAL TRAINING IN PATIENTS WITH MODERATE-TO-SEVERE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)

To evaluate the influence of physical training with or without noninvasive ventilation at 2 levels of pressure in the airways (BiPAP) in patients with chronic obstructive pulmonary disease. Eighteen patients with FEV(1) = 34 +/- 8% of predicted values, mean age of 68 +/- 9 years were randomly distributed into 2 groups, one group performing physical training on a treadmill and the other group performing physical training associated with BiPAP (physical training+B), for 30 minutes, 3 times a week for 12 weeks. The training velocity was based on a test of cardiopulmonary force performed pre- and postintervention, which registered the values for heart rate, systolic blood pressure, diastolic blood pressure, peripheral oxygen saturation, blood lactate, sensation of dyspnea, respiratory muscle strength, and analysis of gases expired such as oxygen consumption and the production of carbon dioxide. For both groups, there was a significant improvement in dyspnea and peripheral oxygen saturation at identical levels of physical exercise, in distance walked during the physical training, and in respiratory muscle strength (P < 0.05). Only the physical training+B group had a significant improvement in heart rate, systolic blood pressure, and oxygen consumption after training (P < 0.05). Significant reductions of blood lactate were observed at identical levels of exercise in physical training+B when compared to isolated physical training (from 1.3 +/- 0.7 mMol/L versus 2.5 +/- 0.9 mMol/L, (P < 0.05), respectively). Physical training associated with BiPAP enhanced the oxidative muscular capacity and could be an adjunctive recourse for physical rehabilitation in patients with chronic obstructive pulmonary disease.

Effect of Xin’ anning Nasal Drop (心安宁滴鼻剂) in treating coronary heart disease with unstable angina pectoris

To observe the clinical efficacy of Xin'anning Nasal Drop (XAND) in treating coronary heart disease with unstable angina pectoris (CHD-UAP). Sixty patients with CHD-UAP were assigned, according to the randomizing number table, to two groups, the control group treated with conventional Western medicine, and the treated group treated with conventional Western medicine plus XAND. The clinical efficacy and the changes of S-T segment in resting EKG and total ischemia burden (TIB) in 24-h dynamic EKG were observed. The clinical efficacy, including the effect of angina alleviation, its initiation, and the effect of TCM syndrome score reduction, were significantly superior in the treated group to those in the control group ( P<0.05 or P<0.01). The degree and extent of myocardial ischemia were significantly improved in both groups ( P<0.01), but the improvement in the treated group was better than that in the control group ( P<0.05). Moreover, it was worth mentioning that the immediate effect in the treated group was better than that in the control group, and the reduction of TIB, the improvement in heart rate and myocardial oxygen consumption (immediately after the first administration or by the end of the therapeutic course), and systolic blood pressure after treatment in the former were all superior to those in the latter, showing significant difference (P<0.05 or P<0.01). XAND has a quick effect in alleviating angina in patients with CHD-UAP, and it is worthy of further studies and spreading in clinical practice. unstable angina pectoris, Xin'anning Nasal Drop, clinical study

Milrinone improves oxygenation in neonates with severe persistent pulmonary hypertension of the newborn

Background Many neonates with severe persistent pulmonary hypertension of the newborn (PPHN) are nonresponders to inhaled nitric oxide (iNO). Milrinone is a promising adjunctive therapy because of its pulmonary vasodilator properties and cardiotropic effects. Design Case series of neonates with severe PPHN (defined as oxygenation index [OI] >20, failure of iNO therapy, and echocardiographic confirmation of PPHN). Setting Tertiary neonatal intensive care unit. Subjects Full-term (≥37 weeks) neonates with severe PPHN who received intravenous milrinone. Measurements The primary end point was the effect of intravenous milrinone on OI and hemodynamic stability over a 72-hour study period. Secondary end points examined included duration of iNO and degree of cardiorespiratory support. Results Nine neonates at a mean gestation of 39.25 ± 2.76 weeks, birth weight of 3668 ± 649.1 g, and baseline OI of 28.1 ± 5.9 received milrinone treatment after a poor initial response to iNO treatment. Intravenous milrinone was commenced at a median age of 21 hours (range, 18-49 hours), and patients were treated for median of 70 hours (range, 23-136). Oxygenation index was significantly reduced after milrinone treatment, particularly in the immediate 24 hours of treatment (8.0 ± 6.6, P < .001). There was a significant improvement in heart rate (179 ± 15.2 vs 149.6 ± 22.4, P < .001) over the same period. Infants who received milrinone did not develop systemic hypotension; in fact, there was a nonsignificant trend toward improved blood pressure. Conclusions Intravenous milrinone produces early improvements in oxygenation without compromising systemic blood pressure.

Part 13: Neonatal Resuscitation Guidelines

The following guidelines are intended for practitioners responsible for resuscitating neonates. They apply primarily to neonates undergoing transition from intrauterine to extrauterine life. The recommendations are also applicable to neonates who have completed perinatal transition and require resuscitation during the first few weeks to months following birth. Practitioners who resuscitate infants at birth or at any time during the initial hospital admission should consider following these guidelines. The terms newborn and neonate are intended to apply to any infant during the initial hospitalization. The term newly born is intended to apply specifically to an infant at the time of birth. Approximately 10% of newborns require some assistance to begin breathing at birth. About 1% require extensive resuscitative measures. Although the vast majority of newly born infants do not require intervention to make the transition from intrauterine to extrauterine life, because of the large number of births, a sizable number will require some degree of resuscitation. Those newly born infants who do not require resuscitation can generally be identified by a rapid assessment of the following 4 characteristics: If the answer to all 4 of these questions is “yes,” the baby does not need resuscitation and should not be separated from the mother. The baby can be dried, placed directly on the mother’s chest, and covered with dry linen to maintain temperature. Observation of breathing, activity, and color should be ongoing. If the answer to any of these assessment questions is “no,” there is general agreement that the infant should receive one or more of the following 4 categories of action in sequence:

Effects of Lidocaine Spray or Lidocaine IV on Endotracheal Intubation during Sevoflurane Inhalation Induction without Muscle Relaxants

Background: This study was designed to assess tracheal intubation without muscle relaxants, especially using 8 vol% sevoflurane. The study was designed to compare heart rate and blood pressure changes induced by a 10% lidocaine spray with that of 1% lidocaine IV and a control. Methods: Sixty patients, ASA I or II, undergoing various surgical procedures, were randomly assigned into three anesthetic pretreatment groups: Group I received routine vital capacity rapid induction with sevoflurane; Group II, inhalation induction with a 10% lidocaine spray 5 minutes before intubation; and Group III, inhalation induction with 1% lidocaine IV injection 2 minute before intubation. Intubating conditions were assessed as acceptable or unacceptable on the basis of a scoring system that depended on the ease of laryngoscopy, vocal cord position, and coughing after endotracheal tube insertion. Heart rate and blood pressure changes in each group were assessed before and after intubation. Results: The overall assessments of the intubating conditions were acceptable in 90%, 95%, and in 95% of patients in groups I, II, and III, respectively. Statistically, supplementing with a lidocaine intravenous injection or a pharyngolaryngeal lidocaine spray did not improve intubating conditions. Moreover, no differences in coughing after intubation, and no improvement in heart rate or in blood pressure changes were observed among the three groups. Conclusions: Sevoflurane inhalation induction without muscle relaxants offers satisfactory intubation, and heart rate and blood pressure changes without the use of lidocaine IV injection, or lidocaine.

Part 11: Neonatal Resuscitation

Part 11: Neonatal Resuscitation

THE EFFECT OF DELAYED COMPLETION OF AN EXERCISE PRESCRIPTION PROGRAMME ON OLDER ENGLISH WOMEN

552 England has seen an increase in prescriptive exercise as a method of managing and preventing some diseases, and improving functional capacity. The sedentary female subjects in this study (n=38) had an average age of 51 years, and were referred by their Doctor to 20 supervised aerobic and resistance exercise sessions, where frequency of attendance was self-regulated. Subjects were screened prior to commencement of the programme, and upon completion of 20 sessions. The number of weeks taken to complete the 20 exercise sessions ranged from 10 to 36 weeks. Results identified a significant negative relationship between weeks taken and FEV1 improvement (P<0.01), and FVC improvement (P<0.05). Significant positive relationships were observed between weeks taken to complete and% body fat difference (P<0.05), and reduction in thigh girth (P<0.05). Positive relationships were also found between improvements in heart rate at the end of a submaximal cycle test, and% body fat improvement (P<0.05), and FEV1 improvement (P<0.05). For the purpose of analysis, the subjects were grouped according to the number of weeks taken to complete the 20 sessions. Group 1 completed between weeks 10-12; group 2, between weeks 13-16; group 3, between weeks 17-19, and group 4, between weeks 25-36. Group 2 showed significant differences for% body fat reduction when compared to groups 3 and 4 (P<0.01). Groups 1 and 3 showed significantly greater thigh girth reductions than group 4 (P<0.01). Further analysis revealed a greater number of small, though statistically significant differences within group 1, than any other group, with group 4 showing no significant improvements between tests. It was concluded that an increased frequency of participation in structured exercise, and an earlier completion of a 20 session exercise programme was associated with more positive outcomes.

THE EFFECTS OF CONTINUOUS INHALATION THERAPY WITH LOW CONCENTRATION OF ISOPROTERENOL IN STATUS ASTHMATICUS

1-isoproterenol hydrochloride is a strong bronchodilator acting on the β-adrenergic receptors. Efficacy of continuous inhalation therapy with isoproterenol has been approved but the optimal concentration of the drug for inhalation is not standardized. We studied the efficacy and safty of continuous inhalation therapy with low-dose isoproterenol for patients with status asthmaticus. The results were as follows;(1) Remarkable improvement of clinical symptoms was seen in 9 of 14 patients (64.3%). Significant adverse effects of the drug, which led prompt discontinuation of the thrapy, were recognized in 2 patients but these adverse effects disappeared promptly after stopping the drug.(2) Significant improvement in heart rate, respiratory rate, PaCo2, O2 saturation and pH was seen within 1 hour after initiation of the therapy.(3) The therapy prevented respiratory failure in most patients at the early stage of the inhalation therapy.(4) There was no difference in improvement in any of the tested concentrations of 7.5-12.5μg/kg/hr.Those results suggested that continuous inhalation therapy with low-dose isoproterenol for the treatment of status asthmaticus is effective and safe.

Treatment of acute intrapartum fetal distress by β2-sympathomimetics

Patients with a diagnosis of severe intrapartum fetal distress by fetal heart rate and capillary blood pH monitoring received β2-sympathomimetics to inhibit uterine contractions (tocolysis) while the obstetric team was preparing to deliver the fetus. Fetal heart rate and acidosis significantly improved after tocolysis; these fetuses were subsequently delivered in very good metabolic and clinical condition. The favorable effect of tocolysis on fetal homeostasis is attributed to the suppression of the ischemic effect of contractions on the placental circulation. The few fetuses having an extremely compromised placental function showed no improvement in heart rate or acidosis with tocolysis and were immediately delivered. Considering the mild side effects observed, the lack of maternal complications, and the remarkable perinatal outcome obtained, we racommend using tocolysis before delivering distressed fetuses.

Trimodal assessment in agoraphobia research: Further observations on heart rate and synchrony/ desynchrony

This paper reports new observations on heart rate and synchrony/desynchrony in the context of 22 chronic agoraphobic patients' trimodal assessment pre and post exposure treatment. The results corroborated previous reports showing weak and/or inconsistent improvement in heart rate, in contrast to significant improvement in behavioral and subjective response systems. Moreover, the results did not support recent suggestions that heartrate reactivity at pretreatment or global categories of synchrony/dysynchrony at posttreatment have important implications for treatment outcome. However, subtypes of dysynchrony based on the direction of divergence between variables had different implications for the clinical response, indicating that simply dichotomizing patients into synchronizers/desynchronizers may be misleading in addition to being uninformative.