Hypothyroidism has various cardiovascular manifestation and exhibits electrocardiographic change. The QT dispersion on surface ECG reflects regional variations in myocardial repolarization. The effect of L-thyroxine treatment on ECG parameters, such as QT dispersion, in patients with primary hypothyroidism were investigated. This study involved 18 patients (3 men, 15 women, ages: 48+/-18 yr) with primary hypothyroidism. All patients were checked with a standard 12-lead ECG before and after L-thyroxine treatment. Various ECG parameters were then measured twice. The mean L-thyroxine treatment duration was 22+/-2.7 months. The mean thyroid-stimulating hormone levels of patients before and after therapy were 40.2+/-29.8 microU/mL, 3.6+/-4.6 microU/mL (p<0.001) and free-T4 levels were 0.44+/-0.38 ng/dL, 1.51+/-0.39 ng/dL (p<0.001). After L-thyroxine treatment, QT interval (395+/-42 vs. 380+/-24 msec, p<0.05), QTc interval (434+/-32 vs. 417+/-23 msec, p<0.05), QT dispersion (45+/-23 vs. 30+/-13 msec, p=0.008), QTc dispersion (49+/-23 vs. 32+/-14 msec, p=0.005) significantly decreased. There were no significant changes in the PR and RR intervals, as well as the QRS duration. Our findings suggest that the thyroid hormone affects ventricular inhomogenicity, and that L-thyroxine replacement therapy may reduce malignant ventricular arrhythmia and sudden cardiac death in primary hypothyroidism.
Thyroxine/*therapeutic use ; Middle Aged ; Male ; Hypothyroidism/*drug therapy/physiopathology ; Humans ; Female ; Electrocardiography/*drug effects ; Adult

OBJECTIVETo observe the clinical efficacy of Xin'anning Nasal Drop (XAND) in treating coronary heart disease with unstable angina pectoris (CHD-UAP).

METHODSSixty 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.

RESULTSThe 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).

CONCLUSIONXAND 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

Administration, Intranasal ; Adult ; Aged ; Angina, Unstable ; drug therapy ; physiopathology ; Electrocardiography ; drug effects ; Female ; Heart Rate ; drug effects ; Humans ; Male ; Medicine, Chinese Traditional ; Middle Aged ; Systole ; drug effects

OBJECTIVETo explore the electrophysiological effects of antiarrhythmic drugs on pacemaker cells of left ventricular outflow tract.

METHODSBy using conventional intracellular microelectrode technique to record action potentials, series antiarrhythmic drugs were used to investigate the electrophysiological features and regularities of spontaneous activity of left ventricular outflow tract.

RESULTS(1) Perfusion with 1 micromol/L quinidine resulted in a significant decrease in rate of pacemaker firing (RPF, P < 0.05), velocity of diastolic depolarization (VDD, P < 0.05), amplitude of action potential (APA, P < 0.05), and maximal rate of depolarization (V(max), P < 0.05), and a marked prolonging in 50% and 90% of duration of action potential (APD50 and APD90, P < 0.05). (2) 1 micromol/L lidocaine decreased RPF, VDD, MDP, APA and V(max) significantly (P < 0.05), shortened APD50 and APD90 notably (P < 0.05). (3) 1 micromol/L propafenone led to a significant decrease in RPF (P < 0.01), VDD (P < 0.05), APA (P < 0.05), V(max) (P < 0.01), and a marked prolonging in APD50 (P < 0.01) and APD90 (P < 0.05). (4) Application of 5 micromol/L propranolol resulted in a significant decrease in RPF and VDD (P < 0.01), MDP and APA (P < 0.01), V(max) (P < 0.05) and a notable prolonging in APD50 and APD90 (P < 0.05). (5) Perfusion with 1 micromol/L amiodarone resulted in a significant decrease in RPF and VDD (P < 0.01), APA (P < 0.01), V(max) (P < 0.05), a marked prolonging in APD50 (P < 0.01) and APD90 (P < 0.05). (6) 1 micromol/L verapamil significantly decreased RPF and VDD (P < 0.01), MDP and APA (P < 0.05), V(max) (P < 0.05), notably prolonged APD50 and APD90 (P < 0.01). (7) 50 micromol/L adenosine significantly decreased RPF and VDD (P < 0.05), APA (P < 0.05), V(max) (P < 0.01), markedly shortened APD50 and APD90 (P < 0.05).

CONCLUSIONAll kinds of antiarrhythmic drugs can decrease the autorhythmicity of guinea pig left ventricular outflow tract. By altering APD50 and APD90, they can affect effective refractory period (ERP) and having a significant effect on autorhythmicity of left ventricular outflow tract.

Animals ; Anti-Arrhythmia Agents ; pharmacology ; Electrocardiography ; Guinea Pigs ; Heart Ventricles ; drug effects

The aim of the research was to evaluate the efficacy and safety associated with Shexiang Tongxin Dropping Pills combined with conventional therapy for patients with coronary heart disease(CHD). We searched 8 electronic databases up to November 2020, including PubMed, Cochrane Library, EMbase, Web of Science, CNKI, Wanfang, VIP and SinoMed. Eligible studies were clinical trials of Shexiang Tongxin Dropping Pills combined with conventional therapy used in the treatment of coronary heart disease(CHD). The Meta-analysis was performed using STATA 15 software. A total of 21 RCTs(n=2 186) were shortlisted for the Meta-analysis. The results of efficacy evaluation showed that the total effective rate of Shexiang Tongxin Dropping Pills combined with conventional therapy was higher than that of conventional therapy of coronary heart disease(RR=1.20, 95%CI[1.15, 1.26], Z=8.63, P<0.001). Furthermore, Shexiang Tongxin Dripping Pills combined with conventional therapy had better effect on electrocardiogram efficacy(RR=1.24, 95%CI[1.16, 1.34], Z=5.98, P<0.001) and the number of angina attacks(SMD=-2.30, 95%CI[-3.47,-1.14], Z=3.88, P<0.001), the duration of angina attack(SMD=-2.31, 95%CI[-3.07,-1.55], Z=5.97, P<0.001), with lower levels of LDL-C(SMD=-0.73, 95%CI[-1.32,-0.14], Z=2.42, P=0.016), TC(SMD=-1.16, 95%CI[-1.35,-0.96], Z=11.56, P<0.001) and TG(SMD=-0.87, 95%CI[-1.06,-0.68], Z=8.97, P<0.001), and higher levels of HDL-C(SMD=0.87, 95%CI[0.02, 1.71], Z=2.00, P=0.045). The results of safety evaluation showed that the incidence of adverse reactions of Shexiang Tongxin Dropping Pills combined with conventional therapy was lower than that of conventional therapy of coronary heart disease(RR=0.45, 95%CI[0.22, 0.91], Z=2.23, P=0.026). There were significant differences in the above outcome indexes between the two groups. After the Harbord method test, the total effective rate outcome index has publication bias, but the sensitivity analysis of the cut-and-fill method suggested that the result was stable. In general, limited by the quantity and quality of included literature, more high-quality studies are needed to further verify the conclusions of this study.
Angina Pectoris ; Coronary Disease/drug therapy* ; Drugs, Chinese Herbal/adverse effects* ; Electrocardiography ; Humans

OBJECTIVETo investigate cardiac effects of arsenic trioxide (As(2)O(3)) at conventional dosage in acute promyelocytic leukemia (APL) patients.

METHODSThe basical heart rate, electrocardiograph, plasma As(2)O(3) concentration of APL patients were dynamically monitored. The action potential duration and current of I(Ca-L) in guinea pig cardiac ventricular myocytes were assayed by patch clamp technique, and the elevated cytosolic [Ca(2+)]i of guinea pig ventricular myocytes induced by As(2)O(3) by laser confocal microscopy.

RESULTSApproximately 52.5% - 35% of 40 APL patients manifested poor cardiac effects of different degree when As(2)O(3) intravenous infused at conventional doses in the initial 1 or 2 weeks with fast heart rate or prolonged QT interval. As(2)O(3) at concentration of 1, 2, 5 micro mol/L prolonged action potential duration from (563.0 +/- 55.8) ms to (737.7 +/- 131.7), (842.4 +/- 115.6) and (1103.2 +/- 96.3) ms respectively (P < 0.05, P < 0.01, P < 0.01), and increased I(Ca-L) of guinea pig cardiac ventricular myocytes as well as the respectively cytosolic [Ca(2+)]i. Calcium channel blocking agent can cut-out the effect.

CONCLUSIONAs(2)O(3) intravenous infusion at conventional doses can cause tachycardia and prolong QT interval. The probable mechanism might be that As(2)O(3) affects the ion channels and cytosolic calcium.

Adult ; Animals ; Antineoplastic Agents ; adverse effects ; Arsenicals ; adverse effects ; blood ; Calcium ; metabolism ; Calcium Channels, L-Type ; drug effects ; Cricetinae ; Electrocardiography ; drug effects ; Female ; Heart ; drug effects ; Humans ; Leukemia, Promyelocytic, Acute ; drug therapy ; Male ; Oxides ; adverse effects ; blood

OBJECTIVETo observe the intervention of Shenfu Injection (SFI) on the hemodynamics and circulatory function during induction of general anesthesia for aged people, in order to optimize the medication of anesthesia inductive phase in aged people.

METHODSSixty aged patients scheduled to receive general anesthesia were equally randomized into 2 groups, the SFI group and the control group. SFI via intravenous drip (1 mL/kg diluted with 5 mL/kg saline) was administered to the SFI group 15 min before anesthesia induction and to the control group, normal saline was administered instead. Then the induction and intubation were implemented. The systolic blood pressure (SBP), diastolic pressure (DBP), heart rate (HR), central venous pressure (CVP), pulse saturation oxygen (SpO2), and the ST segment of ECG were observed at the different time points of induction, i.e. at the time of entry into the operating room (T1), ending the medication (T2), before the induction (T3), showing the lowest SBP in induction (T4), before and after intubation (T5 and T5). The dose and frequency of atropine and ephedrine applied in the inductive phase were observed as well.

RESULTSAs compared with the baseline values measured at T1, CVP elevated at T2, T3, and T6 (P < 0.05), SBP and DBP descended at T4, T5, T6 in both groups; HR accelerated at T2, T3, and T6 in the control group; and HR at T4, T5 and T6 in both groups were significantly different (P < 0.05 or P < 0.01). Inter-group comparisons showed significant difference between groups in CVP at T2 (P < 0.05); so did SBP, DBP and HR at T4, T5 and T6 (P < 0.05 or P < 0.01).

CONCLUSIONApplication of SFI in the inductive phase of general anesthesia in aged people could evidently reduce the fluctuation of hemodynamics to prevent the occurrence of myocardial ischemia and improve it definitely.

Aged ; Anesthesia, Conduction ; Anesthesia, General ; Blood Circulation ; drug effects ; physiology ; Blood Pressure ; drug effects ; Drugs, Chinese Herbal ; therapeutic use ; Electrocardiography ; drug effects ; Female ; Heart Rate ; drug effects ; Hemodynamics ; drug effects ; Humans ; Injections, Intravenous ; Male ; Myocardial Ischemia ; prevention & control ; Phytotherapy

Bupivacaine is widely used as a local anesthetic. Central nervous system (CNS) and cardiovascular toxicity are well known side effects. However, there has been no report of bupivacaine-induced myocardial injury. We present a case of bupivacaine cardiac toxicity mimicking an acute non-ST segment elevation myocardial infarction, which was eventually diagnosed as bupivacaine-induced cardiac toxicity without CNS toxicity. As soon as a healthy young woman at a private clinic was given a spinal anesthesia of 6mg bupivacaine for hemorrhoidectomy, she developed arrhythmia and hypotension. She was transferred to our emergency room. There was an accelerated idioventricular rhythm with ST segment depression on electrocardiogram, coarse breathing sounds with rales on whole lung field and a butterfly sign on the chest radiograph. 2D transthoracic echocardiography (TTE) revealed reduced left ventricle systolic ejection fraction (approximately 27%). There was regional wall motion abnormality of the left ventricle on 2D TTE and the cardiac marker was increased. We diagnosed the patient as having acute non-ST segment elevation myocardial infarction but her impaired cardiac function improved gradually. On the seventh day from admission, there was a complete spontaneous recovery of cardiac function, and coronary angiography revealed a normal coronary artery. Therefore, we firmly believe that bupivacaine directly injures the cardiac cell.
Myocardium/*pathology ; Myocardial Infarction/chemically induced/*diagnosis/etiology ; Humans ; Heart/*drug effects ; Female ; Electrocardiography ; Diagnosis, Differential ; Bupivacaine/*adverse effects ; Adult

OBJECTIVETo investigate the cardiac effect of QT interval prolongation in the treatment of acute promyelocytic leukemia (APL) with arsenic trioxide (As(2)O(3)), and the relationship between QT and serum arsenic concentration.

METHODSBlood serum arsenic concentrations of thirty APL patients were determined at 2 hours, 4 hours, 8 hours, and 24 hours after As(2)O(3) injection using atomic fluorophotometry. Cardiac functions were measured simultaneously using a 12-lead body-surface electrocardiogram (ECG). Q-T intervals were manually measured, and then corrected using Bazett's formula (QTc). QT dispersion (QTd) was also calculated. In order to assess the effects of arsenic on the symptoms of anemia, twenty-four anemia patients were divided into two groups on the basis hemoglobin concentration: Group 1 (Hb > or = 90 g/L), and Group 2 (60 g/L < or = Hb < 90 g/L). QTc and QTd of these patients were also manually measured.

RESULTSAll QT intervals of APL patients treated with As(2)O(3) injection were prolonged [32.2 ms (27, 41 ms); P < 0.05], but the changes of QTd were not prominent [3 ms (-8, 7 ms), P > 0.05]. There was a delay of 2 hours in maximum QTc following peaks in serum arsenic concentration. Changes in QTc and QTd of the two anemic groups were not prominent.

CONCLUSIONSAs(2)O(3) can prolong QTc intervals in APL patients, but the effects are delayed compared to peak serum arsenic concentrations. As(2)O(3) has no prolongation effect on QTd. Mild and moderate anemia do not effect QTc and QTd.

Arsenicals ; pharmacology ; therapeutic use ; Electrocardiography ; drug effects ; Humans ; Leukemia, Promyelocytic, Acute ; drug therapy ; Oxides ; pharmacology ; therapeutic use

The autonomic nervous function, blood pressure, coordinate motor and blood alcohol Concentration (BAG) of twenty-one healthy Han volunteers were examined before and after alcohol intake. The purpose was to assess the acute effects of low and moderate doses of alcohol on their coordinate motor and autonomic nervous function. The results showed that after alcohol intake the subjects' heart rate increased and the total power value (TPV) decreased significantly. After the intake of alcohol at low dose, the parasympathetic nervous function of the subjects lying supoine was inhibited significantly. After the intake of alcohol at moderate dose, both the parasympathetic and the sympathetic nervous functions were inhibited. After the intake of alcohol at low dose, both the systolic pressure and the diastolic pressure of the subjects standing up-right were decreased and the diastolic pressure of those lying supine were also decreased. After the intake of alcohol at moderate dose, the systolic and diastolic pressures of the subjects, either lying supine or standing up-right, were decreased. Some subjects showed ataxia after the intake of alcohol at low dose ,and some showed aggravated ataxia after intake of alcohol at moderate dose of alcohol. There was no relationship of BAG with the degree of changes in autonomic nervous function, blood pressure and ataxia. The results indicated that ataxia was induced to come on and the autonomic nervous function was inhibited in some subjects who had taken low and moderate doses of alcohol ,and the cardiovascular regulation was affected too. These suggested that the increase of alcohol intake is adverse to human body's adaptation to the sharp change of circumstance.
Adult ; Alcohol Drinking ; Autonomic Nervous System ; drug effects ; physiology ; Blood Pressure ; drug effects ; China ; ethnology ; Electrocardiography ; drug effects ; Ethanol ; administration & dosage ; adverse effects ; Female ; Gait Ataxia ; chemically induced ; Heart Rate ; drug effects ; Humans ; Male

OBJECTIVETo investigate the effects of oral administration of low-dose propranolol on heart rate variability (HRV), acceleration capacity (AC), deceleration capacity (DC), and cardiac conduction in the treatment of infantile hemangioma.

METHODSA total of 118 infants with hemangioma (≤1 year) were enrolled, and 24-hour ambulatory electrocardiography was performed before oral administration of low-dose propranolol and after one month of administration. The changes in time-domain indices [standard deviation of all normal sinus RR intervals (SDNN), standard deviation of all mean 5-minute RR intervals (SDANN), root mean squared successive difference (RMSSD), and percentage of successive normal sinus RR intervals >50 ms (PNN50)] and frequency-domain indices [low frequency (LF) and high frequency (HF)] for HRV, AC, and DC were observed, as well as abnormalities in cardiac conduction and other aspects after administration of propranolol.

RESULTSAfter administration of propranolol, the infants had significantly increased SDNN, RMSSD, LF, HF, and PNN50 (P<0.01), and significantly reduced AC, mean heart rate (HR) and minimum HR (P<0.01). The 24-hour ambulatory electrocardiographic findings showed a nonsignificantly higher abnormal rate after administration of propranolol.

CONCLUSIONSIn the treatment of infantile hemangioma, propranolol can inhibit the activity of sympathetic nerve and block cardiac conduction, but without any serious adverse effect.

Administration, Oral ; Electrocardiography ; drug effects ; Female ; Heart Rate ; drug effects ; Hemangioma ; drug therapy ; physiopathology ; Humans ; Infant ; Male ; Propranolol ; pharmacology ; therapeutic use