Bradycardia

Cardiac arrhythmias that are characterized by excessively slow HEART RATE, usually below 50 beats per minute in human adults. They can be classified broadly into SINOATRIAL NODE dysfunction and ATRIOVENTRICULAR BLOCK.

Also Known As:

Networked: 8068 relevant articles (287 outcomes, 429 trials/studies)

Relationship Network

Disease Context: Research Results

Related Diseases

1.	Hypotension (Low Blood Pressure)
2.	Tachycardia (Tachyarrhythmias)
3.	Anoxia (Hypoxia)
4.	Apnea
5.	Hypertension (High Blood Pressure)

Experts

1.	Henderson-Smart, D J: 17 articles (01/2003 - 01/2000)
2.	Crestani, Carlos C: 13 articles (01/2014 - 01/2007)
3.	Colombari, Eduardo: 12 articles (02/2011 - 06/2004)
4.	Resstel, Leonardo B M: 11 articles (04/2015 - 12/2008)
5.	Mendelowitz, David: 10 articles (07/2014 - 01/2002)
6.	Alves, Fernando H F: 10 articles (10/2013 - 12/2008)
7.	Lahlou, Saad: 9 articles (08/2013 - 08/2002)
8.	Machado, Benedito H: 9 articles (06/2007 - 09/2002)
9.	Deshpande, Shripad B: 8 articles (04/2015 - 09/2006)
10.	Webster, William S: 8 articles (11/2014 - 04/2005)

Drugs and Biologics

Drugs and Important Biological Agents (IBA) related to Bradycardia:

1.	Atropine (Hyoscyamine)FDA LinkGeneric 12/01/1987 - "These data evidence that the atropine test is not very helpful in discriminating between an organic and an autonomic involvement of sinus automaticity in patients with sinus bradycardia." 09/01/2015 - "The positive results of atropine test and results of esophageal electrophysiological examination in different ages showed that as age grows, false positive rate of atropine test was significantly reduced, presenting statistically significant difference (x² =6.2821, P<0.05); The positive results of atropine test and results of esophageal electrophysiological examination in different heart rates showed that false positive rate of atropine test on those with bradycardia was smaller than those with significant bradycardia, presenting statistically significant difference (x² =5.1792, P<0.05). " 10/01/2012 - "Bradycardia caused by a vagal response during surgery is not uncommon and routinely treated successfully with administration of atropine-like agents. " 01/01/2001 - "The protective effects of atropine against bradycardia lasted 50 minutes. " 05/01/1992 - "Atropine given i.v. almost totally eliminated the bradycardia and partially prevented the hypotensive responses to intra-HF DA1-8. "
2.	Phenylephrine (Neo-Synephrine)FDA LinkGeneric 05/01/2014 - "In contrast, phenylephrine (PE)-induced rise in MAP evoked markedly attenuated bradycardia with dramatically reduced c-Fos expression in the nucleus tractus solitarius (NTS) of adult OZR compared with LZR. " 04/30/1998 - "The magnitude of the baroreceptor reflex mediated bradycardia, induced by a phenylephrine induced pressor response, was significantly greater in NK1 knockout mice (P < 0.001) compared to heterozygous and wild-type animals. " 11/03/1992 - "Comparable increments in blood pressure evoked by systemic AVP, as opposed to phenylephrine, were associated with significantly greater reflex bradycardia. " 02/01/1988 - "Bradycardia elicited by phenylephrine-induced increases in pressure was significantly greater after NTS injection of [Sar1, Thr8]Ang II. The slope of the pulse interval-arterial pressure relationship was 0.60 +/- 0.09 ms/mm Hg after injection, as compared with 0.42 +/- 0.07 ms/mm Hg before. " 05/01/2012 - "The reduced BRS for bradycardia was associated with a significant decrease in alpha-adrenergic responsiveness to phenylephrine at 60 minutes after PTP1b inhibition. "
3.	OxygenIBA 01/01/1994 - "Bradycardia has been shown to be beneficial for the normal and ischaemic heart because it improves diastolic perfusion and oxygen supply demand balance. " 03/01/1986 - "In contrast, in a dabbling duck (Anas platyrhynchos) bradycardia in short dives was eliminated by breathing oxygen before a dive. " 03/01/1986 - "Bradycardia was unaffected by breathing oxygen before a dive, but was virtually eliminated by local anaesthesia of the narial region. " 01/01/2013 - "The purpose of this study was to compare bradycardia and oxygen desaturation events in preterm infants in standard incubator care versus KC. " 01/01/2012 - "None of the individual studies or the meta-analyses showed a reduction in apnoea, bradycardia, oxygen desaturation or oxygen saturation with body positioning (supine versus prone; prone versus right lateral; prone versus left lateral; right lateral versus left lateral; prone horizontal versus prone head elevated; right lateral horizontal versus right lateral head elevated and left lateral horizontal versus left lateral head elevated). "
4.	Propranolol (Inderal)FDA LinkGeneric 08/01/2009 - "Thus, the bradycardia-propranolol signals calculated in this study were not significant. " 10/01/1980 - "In this study we compared the dose needed to lower blood pressure upon i.c.v. infusion with the dose of 5 mg/kg x day dl-propranolol, which we reported earlier to induce a long lasting bradycardia and antihypertensive effect when infused s.c. " 10/20/1978 - "Four patients had to be excluded from the study because they developed either marked bradycardia or anxiety states or paraesthesias after propranolol (3 x 40 mg/d). " 01/01/2016 - "Although bradycardia and hypotensive events occur early after TBI, low-dose intravenous propranolol does not increase their number or severity. " 01/01/2016 - "We hypothesize that judicious early low-dose propranolol after TBI (EPAT) will improve outcomes without altering bradycardia or hypotensive events. "
5.	Amiodarone (Amiodarona)FDA LinkGeneric 08/13/2007 - "The risk of bradyarrhythmia requiring pacemaker insertion associated with amiodarone use for AF is significantly greater in women than in men, independent of weight or body mass index." 01/01/2007 - "Bradycardia usually improved after lowering of amiodarone dose. " 08/01/2007 - "One-hundred and two patients were included in the study (9 were excluded for bradycardia), and 25 received amiodarone treatment. " 10/01/2006 - "In the first 24 h of treatment with amiodarone, 22 patients (10 men and 12 women) were excluded from the study due to sinus bradycardia. " 01/15/2003 - "This study suggests that the use of amiodarone in elderly patients with AF and a previous MI increases the risk of bradyarrhythmia requiring a permanent pacemaker. "
6.	Clonidine (ST 155)FDA LinkGeneric 06/01/1998 - "In this study, we investigated whether this effect of clonidine is related to facilitation of baroreceptor control of reflex bradycardia. " 01/01/1993 - "On the other hand, both low and high doses of clonidine induced bradycardia in the in vivo as well as in vitro studies." 01/01/2012 - "PVN injection of clonidine induced a dose-dependent pressor response concomitant with bradycardia. " 01/01/2012 - "Microinjection of the α(2)-adrenoceptor agonist clonidine into the hypothalamic periventricular nuclei (PVN) induces the pressor response associated with bradycardia in freely-moving conscious rats. " 02/01/2008 - "Physicians prescribing clonidine should monitor for bradycardia and advise patients about the high likelihood of initial drowsiness."
7.	Atenolol (Tenormin)FDA LinkGeneric 01/01/2007 - "The hybrid therapy adopted, OAS associated with the use of atenolol, reduced the rate of recurrent AF and improved the clinical-functional status of patients with symptomatic bradyarrhythmias." 01/01/1990 - "The administration of beta-adrenoceptor blockade (1.0 mg/kg atenolol) improved regional contractile function when heart rate was reduced from 220 to 165 beats/min. Atrial pacing during exercise to prevent the bradycardia following beta-adrenoceptor blockade eliminated the improved regional function and blood flow. " 01/01/1981 - "Two patients had to be withdrawn from the study during treatment with atenolol, as they developed severe bradycardia and dyspnoea, respectively. " 12/01/2011 - "Both treatment regimens reduced mean blood pressure in a similar fashion, while bradycardia was present only in atenolol-treated SHRs. " 12/01/2010 - "Atenolol was immediately discontinued, with a continuance of the bradycardia despite one missed dose. "
8.	DexmedetomidineFDA Link 01/01/2012 - "Despite the fact that more dexmedetomidine-treated patients developed bradycardia (18.2% vs. 0, p=0.016), no patients required an intervention or interruption of study drug infusion. " 06/01/2010 - "Dexmedetomidine was associated with increased risk of bradycardia requiring interventions in studies that used both a loading dose and maintenance doses >0.7 microg kg(-1) h(-1) [relative risk (RR) 7.30, 95% CI 1.73-30.81, P = 0.007]. " 02/01/1991 - "Bradycardia was very modest after dexmedetomidine in this study, and thus no reversal of alpha 2-adrenoceptor agonist-induced bradycardia could be demonstrated. " 12/01/2015 - "However, these effects are confounded by dexmedetomidine-induced bradycardia. " 07/01/2015 - "Need for rescue drug for achieving the desired RSS as well as incidence of bradycardia was more in dexmedetomidine group than other. "
9.	Serotonin (5 Hydroxytryptamine)IBA 03/01/1983 - "Vagal blockade eliminated the bradycardia but otherwise did not alter the response to left atrial serotonin. " 11/01/2007 - "6. In conclusion, in the present study, experimental diabetes evoked changes in both the nature and 5-HT receptor types/subtypes involved in vagally induced bradycardia." 04/01/1997 - "In the present study, we analyzed in conscious rats the effects of microinjections of serotonin (5-HT; pmol range) into the nucleus of the solitary tract (NTS) on basal mean arterial pressure (MAP) and heart rate (HR) and also on the reflex bradycardia induced by the activation of the baro- and chemoreflex evaluated 1 min after 5-HT microinjection into the NTS. " 03/01/1986 - "This study has demonstrated, therefore, that the 5-HT induced bradycardia is produced by not only a centrally mediated decrease in sympathetic tone, but also an increase in vagal drive to the heart. " 09/01/2014 - "Subsequent i.c.v. injection of 5-HT produced a minor pressor response (+7±2%), bradycardia (-18±3%), an increase in MR (+52±8%) but no decreases in RR or HQR. "
10.	bipiperidyl mustard (BPM)IBA 05/30/2007 - "Exercise training induced resting bradycardia (340+/-5 vs. 316+/-8 bpm) and improvement in baroreflex tachycardic response (3.4+/-0.31 vs. 2.7+/-0.06 bpm/mmHg in SC) and chemoreflex bradycardic (145+/-12 vs. 78+/-7 bpm in SC) and pressor (49+/-5 vs. 22+/-3 mmHg in SC) responses in control rats. " 09/01/2013 - "We retrospectively calculated the fetal bradycardia area in the last 60 min before delivery with an upper limit of 90 bpm and correlated the area with neonatal pH. The study of the regression line determined the cut-off threshold between fetal well-being and distress. " 07/01/2008 - "The primary study variable was the combined event rate of desaturations (SpO2 <85%) and bradycardias (heart rate <80 bpm). " 12/01/2015 - "Symptomatic reflex bradycardia was defined as a sudden decrease in heart rate to <50 beats per minute (bpm), or to 50-59 bpm with a systolic blood pressure <70 mmHg, associated with a specific surgical maneuver. " 11/01/2015 - "No severe bradycardia (<60 bpm) was noticed. "

Therapies and Procedures

1.	Injections 12/01/1974 - "Bradycardia persisting after cholinergic blockade was significantly greater after injections into the coronary artery supplying the sinus node than it was after injections into the contralateral artery. " 07/01/2010 - "Despite central vasodilatation, bradycardia, and decrease of FS and average volumetric flow (VFave), mean arterial blood pressure did not significantly decrease indicating well-preserved cardiovascular compensatory mechanism after the ratio and doses of KET-XYL IV bolus injections used in this study." 09/01/2005 - "Peribulbar injections cause further increases in blood pressure and mild bradycardia. " 12/01/2003 - "Bilateral intra-NTS injections of CART antibody (1:500) potentiated PE-induced bradycardia. " 12/01/1998 - "Bradycardia, augmentation of ventricular contractions, and reduction of perfusion pressure were prominent responses to bolus injections of NKA (0. "
2.	Vagotomy 06/01/1987 - "The CIM bradycardia was not affected by supracollicular decerebration, but substantially reduced by unilateral vagotomy and completely eliminated by bilateral vagotomy. " 01/01/2015 - "The time-matched heart rate changes (bradycardia) and respiratory changes (tachypnea in delayed phase) were abolished after vagotomy. " 11/02/2012 - "Furthermore, vagotomy reduced the bradycardia in WKY and SHR (-136 ± 8 vs -17 ± 2, n=4, p<0.05; -141 ± 9 vs -8 ± 2, n=6, p<0.05). " 01/01/2011 - "Bilateral vagotomy abolished ANG-(1-12)-induced bradycardia. " 02/01/2009 - "A bilateral vagotomy completely abolished Ucn3-induced bradycardia. "
3.	Resuscitation 10/01/2015 - "Combined HH caused acute bradycardia that was reversed by fluid resuscitation. " 02/01/2015 - "During the procedure the patient had severe desaturation and bradycardia requiring resuscitation fortwo minutes. " 01/01/2014 - "A cornerstone of neonatal resuscitation teaching suggests that a rapid vagal-mediated bradycardia is one of the first signs of perinatal compromise. " 01/01/2011 - "In this report, the authors describe a case of successful neonatal resuscitation after caesarean delivery in a severe growth-restricted fetus with absent cardiac activity following prolonged intrauterine bradycardia. " 05/01/2009 - "At birth, resuscitation efforts were instituted because of a lack of spontaneous breathing and bradycardia. "
4.	Anesthesia 05/01/1994 - "This study sought to determine the frequency of bradycardia during anesthesia in infants (0 to 1 yr) compared to that in older children, describe causes and morbidity, and identify factors that influence its frequency. " 12/01/2015 - "There is a correlation of severity of bradycardia and slightness of anesthesia.In" 10/01/2011 - "REC commonly was precipitated by anesthesia-related events (ie, intubation, extubation, and treatment of bradycardia). " 06/01/2011 - "The latter two protocols induced a deep plane of anesthesia more consistently but also more significant bradycardia. " 03/01/2010 - "Severe bradycardia after anesthesia before electroconvulsive therapy."
5.	Cardiac Resynchronization Therapy 10/01/2011 - "Biventricular pacing is superior to right ventricular pacing in bradycardia patients with preserved systolic function: 2-year results of the PACE trial." 11/26/2009 - "In this study, we examined whether biventricular pacing is superior to right ventricular apical pacing in preventing deterioration of left ventricular systolic function and cardiac remodeling in patients with bradycardia and a normal ejection fraction. " 06/01/2007 - "Methods PREVENT-HF is an ongoing multicentre randomized controlled pilot study designed to assess whether biventricular pacing is superior to RV pacing in patients receiving a bradycardia pacemaker for standard indications. " 04/01/2015 - "Because he had no indications for bradycardia pacing or biventricular pacing, he was implanted with a subcutaneous ICD under full anticoagulation. " 03/01/2015 - "Biventricular pacing for bradycardia: are we there yet?"