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Hamdan A, Saxena A, Rao G, Ivanov M. Compression of a giant pseudomeningocele causing transient anoxic seizures-a case report. Acta Neurochir (Wien) 2018; 160:479-485. [PMID: 29299677 DOI: 10.1007/s00701-017-3446-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 12/21/2017] [Indexed: 11/28/2022]
Abstract
Transient anoxic seizure upon application of pressure on a giant pseudomeningocele has never been reported in the literature; such abrupt changes in intracranial pressure due to large volume of cerebrospinal fluid (CSF) translocation, if left untreated may lead to permanent cerebral hypoxic injury and death. Here we describe a case of a 26-year-old woman who had undergone lumbar disc surgery in another unit few months ago and developed a large lump around her back. Any pressure on the lump resulted in headaches and at times episodes of seizures. Clinical examination revealed a very large fluid-filled lump consistent with a giant pseudomeningocele, confirmed by an MRI. A video EEG while applying pressure on the lump was recorded. The patient developed a typical seizure attack with a characteristic pattern of cerebral anoxia, and a paired ECG showed irregular rhythm with junctional and ventricular ectopic beats during the latter part of the attack, raising a suspicion of asystole. Upon relieving the pressure off the lump, the patient gradually regained consciousness with no permanent neurological deficit. We then discuss the pathophysiology of anoxic seizures and highlight the need to be vigilant in managing patients with such lesions in order to prevent permanent cerebral hypoxic injury and death.
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Affiliation(s)
- Alhafidz Hamdan
- Department of Spinal Surgery, Northern General Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK.
| | - A Saxena
- Department of Neurosurgery, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
| | - G Rao
- Department of Neurosurgery, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
| | - M Ivanov
- Department of Spinal Surgery, Northern General Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
- Department of Neurosurgery, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
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Mbarek D, Naccache S, Abdallah M, Tlili R, Ben Ameur Y, Boujnah MR. Hisian extrasystole mimicking second degree atrioventricular block. a case report. Tunis Med 2017; 95:145-148. [PMID: 29424877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Hisian extrasystoles originate from the His bundle. They are rare and usually misdiagnosed. In fact, they manifest on the EKG, with a p' wave located before, in or after the QRS complex. More rarely, the extrasystole blocks the propagation of the influx to the ventricles simulating a Mobitz II atrioventricular (AV) block. We report the case of a 36-Year-old woman with no medical History, suffering from presyncope and palpitations at rest. Her physical examination and EKG were normal. The 24-hour Holter monitoring showed some long periods with unexpected blocked p waves but with no significant pause. Considering her young age and the absence of causes of AV block, we performed an intracardiac electrophysiological study which showed hisian extrasystoles with normal conduction tissue properties at baseline and under flecainide. The diagnosis of hisian extrasystoles simulating Mobitz II AV block was made. A simple monitoring with beta-blockers therapy was recommended. Hisian extrasystoles may simulate first or second degree AV block with different therapeutic and prognostic implications. Nevertheless, these hisian extrasystoles may be the marker of a vulnerable AV conduction, long-term follow up should be considered.
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Pellizzón OA, Elizari MV. [Trigeminy of ventricular bigeminy caused by reentrant mechanism: reentry of reentry]. Medicina (B Aires) 2017; 77:515-518. [PMID: 29223947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023] Open
Abstract
The process that follows an acute myocardial infarction generates an appropriate substrate for the formation of reentry circuits, considered to be the most frequent mechanism of ventricular extrasystoles and tachyarrhythmias. We present the case of a patient with an acute myocardial infarction unusually concurring with ventricular trigeminy coupled to ventricular bigeminated extrasystoles giving rise to a trigeminy sequence over the bigeminy, which indicates the existence of two reentry circuits (reentry of reentry) that trigger ventricular flutter.
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Affiliation(s)
- Oscar A Pellizzón
- Unidad Coronaria y Centro de Arritmias Cardíacas, Hospital Universitario del Centenario, Facultad de Ciencias Médicas, UNR, Rosario, Santa Fe, Argentina. E-mail:
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Wizemann V, Kramer W, Thormann J, Kindler M, Schütterle G. Cardiac arrhythmias in patients on maintenance hemodialysis: causes and management. Contrib Nephrol 2015; 52:42-53. [PMID: 2436852 DOI: 10.1159/000413123] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Abstract
Adult subjects with high-grade VEA have an increased risk of sudden death. In all likelihood, the risk reflects a predisposition to VF with concomitant but possibly independently caused VEA. Among patients sustaining acute myocardial infarction, the severity of VEA late after infarction appears to depend primarily on the extent of underlying coronary artery disease and the extent of tissue damage sustained, as does the likelihood of sudden death. It is not yet clear whether suppression of one manifestation of severe coronary artery disease, namely VEA, confers protection against more serious manifestations - particularly sudden death. Although increased mortality among patients with and without overt coronary artery disease is associated with high-grade VEA and although the absolute frequency of PVCs is strongly correlated with severity defined with conventional classification schemes, frequent, unifocal PVCs in the absence of high-grade VEA appear to carry only a small associated risk of sudden death [56]. Furthermore, even though early PVCs may be particularly hazardous soon after the onset of acute myocardial infarction, they do not appear to be malignant during the hospital phase or among ambulatory patients with or without coronary artery disease. The temptation to suppress even low-grade VEA is strong because even a single PVC can initiate VF in the ischemic heart, and it is of course possible that suppression could prevent a single PVC from occurring after the onset of ischemia and initiating VF. However, suppression of PVCs, even if successful in an ambulatory patient, will not necessarily suppress VEA initiated by a new bout of ischemia. Accordingly, based on currently available information, low-grade VEA does not require treatment in our view in ambulatory patients without specific indications.
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Gao M, Cui Z. [Effect of bronchoalveolar lavage on the heart rhythm and conduction of the children with severe pneumonia]. Zhonghua Er Ke Za Zhi 2014; 52:252-256. [PMID: 24915909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To observe the effect of bronchoalveolar lavage on the heart rhythm and conduction of children with severe pneumonia through monitoring the electrocardiogram change of different step of the bronchoalveolar lavage, for proving the safety of the operation of bronchoalveolar lavage from the perspective of cardiac electrophysiology. METHOD From July 2011 to March 2012, 30 patients who were hospitalized in pneumology department of Dalian Children's Hospital and met the inclusion criteria and therapeutic indications of bronchoalveolar lavage were chosen. They were 3 to 12 years old, the average age was 5.3 years, including 17 boys and 13 girls, the ratio of boys and girls is 1.3: 1. Continuous sampling the electrocardiogram before and during the process including anesthesia, entering into glottis, lavage, aspiration, and revive, and recording the heart rate, rhythm amplitude and width of P wave, the PR interval, the form and width of QRS complex were also measured. The recorded data were analyzed and statistical analysis to reflect the change of the cardiac electrophysiology. RESULT The incidence of heart rate increase was 100.0%, 26 (86.7%) patients began to emerge after anesthesia, the rest of the patients also developed heart rate increase after the start of bronchoscopic operation. All patients had sinus tachycardia, and were most obvious in the progress of lavage and revive. In the process of entering into glottis, lavage, aspiration, 13 (43.3%) patients had arrhythmia episodes. Types of arrhythmia included sinus bradycardia, atrioventricular block and premature beat. Incidences of intraoperative arrhythmia compared with the pre- and post-operation were all statistically significantly different (P = 0.00). The most common arrhythmia were premature beat, in 17 of the 30 cases there were premature beat including 9 cases with atrial premature beats and 8 cases ventricular premature contraction. Two patients had III° atrioventricular block accompanied by serious sinus bradycardia. All kinds of arrhythmias except sinus tachycardia disappeared after the operation was ended. Five patients (16.7%) had PR interval prolongation. Five patients (16.7%) had incomplete right bundle branch block (IRBBB) . Incidences of IRBBB compared with the pre-operation and post-operation were all not significantly different [13.3% (n = 4) vs. 0(n = 0) and 3.3% (n = 1), all P > 0.05]. Different operating progress made no significant difference in the measurement value of electrocardiogram[13.3% (n = 4) vs. 0(n = 0) and 3.3% (n = 1), all P > 0.05], but showed the most notable effect on heart rate. CONCLUSION Bronchoalveolar lavage can influence the heart rhythm and conduction, but most of the influence with pathological significance are transient. Cardiac electrophysiological changes were the most obvious in endotracheal operation with the risk of malignant arrhythmia but the risk is low, the bronchoalveolar lavage technique is safe. The contingency plans for dealing with all kinds of adverse reactions must be ready before the operations of bronchoalveolar lavage. During the procedure, the patient's ECG changes should be closely monitored to reduce the incidence of adverse reactions.
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Affiliation(s)
- Minglei Gao
- Comprehensive Heart Department, Dalian Children's Hospital, Dalian 116012, China
| | - Zhenze Cui
- Pneumology Department, DaLian Children's Hospital, Dalian 116012, China. (
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Alpert JS. 'Doctor, my heart keeps skipping a beat'. Am J Med 2013; 126:367. [PMID: 23582930 DOI: 10.1016/j.amjmed.2012.11.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 11/29/2012] [Indexed: 12/01/2022]
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Hanaki N. [Accidental poisoning by Nicotiana glauca: a case report]. Chudoku Kenkyu 2012; 25:253-4. [PMID: 23057406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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Zhang T, Bai J, Wang W, Wang D, Shen B. Preliminary study of prospective ECG-gated 320-detector CT coronary angiography in patients with ventricular premature beats. PLoS One 2012; 7:e38430. [PMID: 22701639 PMCID: PMC3368870 DOI: 10.1371/journal.pone.0038430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 05/09/2012] [Indexed: 11/25/2022] Open
Abstract
Background To study the applicability of prospective ECG-gated 320-detector CT coronary angiography (CTCA) in patients with ventricular premature beats(VPB), and determine the scanning mode that best maximizes image quality and reduces radiation dose. Methods: 110 patients were divided into a VPB group (60 cases) and a control group (50 cases) using CTCA.All the patients then underwent coronary angiography (CAG) within one month. CAG served as a reference standard through which the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CTCA in diagnosing significant coronary artery stenosis (luminal stenosis ≥50%) could be analyzed. The two radiologists with more than 3 years’ experience in cardiac CT each finished the image analysis after consultation. A personalized scanning mode was adopted to compare image quality and radiation dose between the two groups. Methodology/Principal Findings At the coronary artery segment level, sensitivity, specificity, PPV, and NPV in the premature beat group were 92.55%, 98.21%, 88.51%, and 98.72% respectively. In the control group these values were found to be 95.79%, 98.42%, 90.11%, and 99.28% respectively. Between the two groups, specificity, sensitivity PPV, NPV was no significant difference. The two groups had no significant difference in image quality score (P>0.05). Heart rate (77.20±12.07 bpm) and radiation dose (14.62±1.37 mSv) in the premature beat group were higher than heart rate (58.72±4.73 bpm) and radiation dose (3.08±2.35 mSv) in the control group. In theVPB group, the radiation dose (34.55±7.12 mSv) for S-field scanning was significantly higher than the radiation dose (15.10±1.12 mSv) for M-field scanning. Conclusions/Significance With prospective ECG-gated scanning for VPB, the diagnostic accuracy of coronary artery stenosis is very high. Scanning field adjustment can reduce radiation dose while maintaining good image quality. For patients with slow heart rates and good rhythm, there was no statistically significant difference in image quality.
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Affiliation(s)
- Tong Zhang
- Department of Radiology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Jinquan Bai
- Department of Radiology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Wei Wang
- Department of Radiology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China
- Department of MRI Room, The First Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Dan Wang
- Department of Radiology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Baozhong Shen
- Department of Radiology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin, China
- * E-mail:
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Sapa J, Nowaczyk A, Kulig K. Antiarrhythmic and antioxidant activity of novel pyrrolidin-2-one derivatives with adrenolytic properties. Naunyn Schmiedebergs Arch Pharmacol 2010; 383:13-25. [PMID: 20949258 PMCID: PMC3016165 DOI: 10.1007/s00210-010-0566-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Accepted: 09/20/2010] [Indexed: 11/26/2022]
Abstract
A series of novel pyrrolidin-2-one derivatives (17 compounds) with adrenolytic properties was evaluated for antiarrhythmic, electrocardiographic and antioxidant activity. Some of them displayed antiarrhythmic activity in barium chloride-induced arrhythmia and in the rat coronary artery ligation-reperfusion model, and slightly decreased the heart rate, prolonged P–Q, Q–T intervals and QRS complex. Among them, compound EP-40 (1-[2-hydroxy-3-[4-[(2-hydroxyphenyl)piperazin-1-yl]propyl]pyrrolidin-2-one showed excellent antiarrhythmic activity. This compound had significantly antioxidant effect, too. The present results suggest that the antiarrhythmic effect of compound EP-40 is related to their adrenolytic and antioxidant properties. A biological activity prediction using the PASS software shows that compound EP-35 and EP-40 can be characterized by antiischemic activity; whereas, compound EP-68, EP-70, EP-71 could be good tachycardia agents.
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Affiliation(s)
- Jacek Sapa
- Department of Pharmacodynamic, Laboratory of Pharmacological Screening, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland.
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Areskog NH, Björk L, Björk VO, Hallén A, Ström G. Physical work capacity, Ecg reaction to work test and coronary angiogram in coronary artery disease. Acta Med Scand Suppl 2009; 472:9-35. [PMID: 4166640 DOI: 10.1111/j.0954-6820.1967.tb12611.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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12
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Dyckner T, Wester PO. Ventricular extrasystoles and intracellular electrolytes in hypokalemic patients before and after correction of the hypokalemia. Acta Med Scand 2009; 204:375-9. [PMID: 82374 DOI: 10.1111/j.0954-6820.1978.tb08458.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fifty-four initially hypokalemic patients, 43 of whom were on diuretic treatment, were given potassium supplementation until they showed a repeatedly normal serum potassium level. Muscle specimens obtained by percutaneous biopsy revealed that there were no concomitant increases in muscle potassium content, nor in intracellular potassium concentration, except in the very small group (6 patients) with a muscle magnesium content of greater than or equal to 3.95 mmol/100 g fat free dry solids (FFDS) and an initially lower muscle potassium content (less than or equal to 39.9 mmol/100 g FFDS). ECG, registered for 3 hours on a portable ECG tape recorder before and after correction of the serum potassium level, showed no change in the frequency of ventricular ectopic beats.
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Wujtewicz MA, Owczuk R, Bieniaszewski L, Suchorzewska J, Wujtewicz M. [The use of heart rate variability analysis to determine changes in autonomic nervous system activity induced by laryngoscopy and endotracheal intubation]. Anestezjol Intens Ter 2008; 40:148-151. [PMID: 19469114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BACKGROUND Laryngoscopy and intubation are associated with marked autonomic system activation that can be assessed by heart rate variability analysis (HRV)--a new method, comparing R-R intervals in 12-lead continuous ECG recording. METHODS Fifty-two ASA I and II adults patients of both sexes were enrolled in the study. Patients were induced with fentanyl and thiopental, paralysed with vecuronium, and intubated. Continuous ECG was recorded and selected time-domain parameters (RMSSD, SDNN, NN50 and pNN50) were analyzed before and after intubation at 5- min intervals. RESULTS Endotracheal intubation resulted in transient supraventricular and ventricular extrasystoles in six patients. Seven patients developed transient bigeminy. Equivocal changes of RMSSD, SDNN, NN50 and pNN50 were observed. CONCLUSION Because of the large incidence of cardiac rhythm disturbances, the HRV proved to be useless for assessment of autonomic system changes.
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Dykukha IS, Artamonov MV, Zhukov OD, Nizhenkivs'kyĭ OI, Rudenko SV, Lyzohub VH, Hula NM. [Phospholipids composition of the myocardium in patients with ischemic heart disease and its connection to arrhythmias]. Ukr Biokhim Zh (1999) 2008; 80:118-123. [PMID: 18959036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The purpose of this study was to establish phospholipid composition of the myocardium in patients with ischemic heart disease, and to estimate possible correlation of biochemical parameters with myocardium extrasystolic activity. The patients (n = 28) including 15 patients with ischemic heart disease and 13 patients with secondary atrium septum defect (control group) were studied. During surgical intervention the right atrium myocardium bioptates were taken. Phospholipid metabolism was studied in the myocardium samples. At the eve of surgical intervention a holter monitoring was performed. Deep changes in the myocardium lipid metabolism were found, including accumulation of free and estherified cholesterol, lysophospholipids, and sphingomyeline. An increase of free cholesterol content was accompanied by accumulation of sphingomyeline. This can be an evidence of changes in the constitution of lipid rafts. Extrasystoles, particularly ventricular ones, in patients with ischemic heart disease might depend on accumulation of lysophospholipids as they took place simultaneously with it.
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Baranchuk A, Ribas S, Divakaramenon S, Morillo CA. An unusual mechanism causing inappropriate implantable cardioverter defibrillator shocks: transient reduction in R-wave amplitude. ACTA ACUST UNITED AC 2007; 9:694-6. [PMID: 17478463 DOI: 10.1093/europace/eum056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Inappropriate shocks delivered by the implantable cardioverter defibrillator (ICD) are an increasingly recognized complication. The most frequent cause is related to supraventricular rhythms associated with fast conduction to the ventricles that are incorrectly detected as ventricular tachycardia leading to inappropriate antitachycardia pacing and/or shocks. Oversensing is a frequent cause of inappropriate shocks usually due to increased amplitude of the T-wave secondary to ischaemia or electrolyte disorders that lead to T-wave double counting. We describe an unusual case of T-wave double counting during sinus rhythm caused by transient reduction in R-wave amplitude with no changes in T-wave amplitude resulting in inappropriate shocks.
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Affiliation(s)
- Adrian Baranchuk
- Arrhythmia Service, McMaster University, Hamilton Health Sciences Corporation, Hamilton, Ontario, Canada.
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Vaswani Dadlani A, González Rojas JC, Arranz Duŕan J, Hernández Afonso J. [Diagnosis of supraventricular tachycardia during surgical correction of pectus carinatum]. Rev Esp Anestesiol Reanim 2007; 54:193-5. [PMID: 17436660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
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Strate T, Mann O, König A, Bachmann K, Izbicki JR. [Arterio-venous aneurysm of splenic vessels--a rare differential diagnosis for cardio-circulatory symptoms]. Zentralbl Chir 2007; 132:77-80. [PMID: 17304441 DOI: 10.1055/s-2006-960489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Patients with arterio-venous fistula of the splenic hilum seek medical assistance because of abdominal discomfort and symptoms of portal hypertension. We report on a 43 year old female who was diagnosed with an arterio-venous aneurysm after suffering from dyspnoea, tachycardia and extrasystolies for several years. After uncomplicated distal splenopancreatectomy the patient was discharged free of symptoms.
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Affiliation(s)
- T Strate
- Klinik und Poliklinik für Allgemein-, Viszeral-, und Thoraxchirurgie, Hamburg.
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Chou CC, Zhou S, Hayashi H, Nihei M, Liu YB, Wen MS, Yeh SJ, Fishbein MC, Weiss JN, Lin SF, Wu D, Chen PS. Remodelling of action potential and intracellular calcium cycling dynamics during subacute myocardial infarction promotes ventricular arrhythmias in Langendorff-perfused rabbit hearts. J Physiol 2007; 580:895-906. [PMID: 17272354 PMCID: PMC2075460 DOI: 10.1113/jphysiol.2006.120659] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We hypothesize that remodelling of action potential and intracellular calcium (Ca(i)) dynamics in the peri-infarct zone contributes to ventricular arrhythmogenesis in the postmyocardial infarction setting. To test this hypothesis, we performed simultaneous optical mapping of Ca(i) and membrane potential (V(m)) in the left ventricle in 15 rabbit hearts with myocardial infarction for 1 week. Ventricular premature beats frequently originated from the peri-infarct zone, and 37% showed elevation of Ca(i) prior to V(m) depolarization, suggesting reverse excitation-contraction coupling as their aetiology. During electrically induced ventricular fibrillation, the highest dominant frequency was in the peri-infarct zone in 61 of 70 episodes. The site of highest dominant frequency had steeper action potential duration restitution and was more susceptible to pacing-induced Ca(i) alternans than sites remote from infarct. Wavebreaks during ventricular fibrillation tended to occur at sites of persistently elevated Ca(i). Infusion of propranolol flattened action potential duration restitution, reduced wavebreaks and converted ventricular fibrillation to ventricular tachycardia. We conclude that in the subacute phase of myocardial infarction, the peri-infarct zone exhibits regions with steep action potential duration restitution slope and unstable Ca(i) dynamics. These changes may promote ventricular extrasystoles and increase the incidence of wavebreaks during ventricular fibrillation. Whereas increased tissue heterogeneity after subacute myocardial infarction creates a highly arrhythmogenic substrate, dynamic action potential and Ca(i) cycling remodelling also contribute to the initiation and maintenance of ventricular fibrillation in this setting.
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Affiliation(s)
- Chung-Chuan Chou
- Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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Sumin AN, Beresneva VL, Enina TN, Verkhoshapova TN, Kabova EA, Valeeva VI, Shapaurina NV. [Factors influencing the effectiveness of physical rehabilitation after myocardial infarction]. Klin Med (Mosk) 2007; 85:24-9. [PMID: 17665599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The aim of the study was to compare initial clinical, hemodynamic, and vegetative parameters in patients with myocardial infarction (MI) who had undergone physical rehabilitation with different results. The subjects were 106 male patients aged 48.6 +/- 0.95 years undergoing sanatorium rehabilitation after MI. According to the dynamics of exercise tolerance (ET) during the course of treatment, the subjects were divided into three groups: group one consisted of 39 patients with a significant ET growth of more than 10W, group two consisted of 47 patients with no changes in ET or its insignificant growth of less than 10W, and group three consisted of 20 patients with a decrease in ET revealed during a repeated test. In group three patients, the initial EchoCG examination revealed a higher degree of myocardial lesion, which was manifested by lowered ejection fraction and sphericity index, increased end-diastolic volume, and increased degree of left ventricular (LV) asynergy. Furthermore, day-time ventricular extrasystoles were more frequent in these patients; the number of patients with large-focal MI, LV aneurysm, and post-infarction stenocardia was also higher in group three. Correlation and multiple step regression analysis revealed that both initial parameters of vegetative nervous system, data from initial load test, and the EchoCG measurements of the right atrium were associated with the degree of ET growth according to VEM results. The data from the study are able to help individualize rehabilitation of MI patients, especially those with severe myocardial lesion.
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Jiménez-Caballero PE, Serviá M, Cabeza CI, Marsal-Alonso C, Alvarez-Tejerina A. [Chronic progressive external ophthalmoplegia: clinical and electromyographic manifestations in a series of cases]. Rev Neurol 2006; 43:724-8. [PMID: 17160922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
INTRODUCTION Chronic progressive external ophthalmoplegia (CPEO) is a common mitochondrial disease. The different conditions in this group of diseases overlap clinically, enzymatically and genetically. There is no effective treatment. Ptosis improves with corrective surgery involving tarsorrhaphy as a palliative measure. CASE REPORTS Code numbers were examined in a retrospective study conducted in order to search for patients with ptosis or ophthalmoplegia who had either visited or been admitted to the neurology department over the last 10 years. Data concerning these patients' clinical features and results of complementary tests were collected. Six patients with CPEO were identified, five of whom were females. Ages ranged from 44 to 72 years. All the patients had ptosis, although 50% were asymmetric. Half of them reported mild dysphagia while swallowing liquids. Levels of creatine phosphokinase and acetylcholine antireceptor antibodies were normal. Half the patients showed increased jitter and a muscle biopsy revealed that five of them had ragged red fibres. The most frequent enzyme deficit was complex I and IV deficiency. There were no familial forms; the most common genetic anomaly was single deletion in the mitochondrial deoxyribonucleic acid. CONCLUSIONS In cases of ptosis and ophthalmoplegia that do not respond to anticholinesterases, knowledge of this condition makes it possible to avoid the use of immunosuppressant drugs, which have important side effects.
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Espinola-Zavaleta N, Soto ME, Castellanos LM, Játiva-Chávez S, Keirns C. Non-compacted cardiomyopathy: clinical-echocardiographic study. Cardiovasc Ultrasound 2006; 4:35. [PMID: 17002802 PMCID: PMC1592122 DOI: 10.1186/1476-7120-4-35] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2006] [Accepted: 09/26/2006] [Indexed: 12/04/2022] Open
Abstract
The aim of the present study was to describe the clinical and echocardiographic findings of ventricular noncompaction in adult patients. Fifty-three patients underwent complete clinical history, electrocardiogram, Holter and transthoracic echocardiogram. Forty patients (75%) were in class I/II of the New York Heart Association, and 13 (25%) in class III/IV. Ventricular and supraventricular escape beats were found in 40% and 26.4%, respectively. Holter showed premature ventricular contractions in 32% and sustained ventricular tachycardia in 7.5%. Ventricular noncompaction was an isolated finding in 74% of cases and was associated with other congenital heart disease in 26%. Noncompacted ventricular myocardium involved only left ventricle in 62% of the patients and both ventricles in 38%. The mean ratio of noncompacted to compacted myocardial layers at the site of maximal wall thickness was 3.4 ± 0.87 mm (range 2.2–7.5). The presence of ventricular noncompaction in more than three segments was associated with a functional class greater than II and ventricular arrhythmia with demonstrable statistical significance by χ2(p < 0.003).
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Affiliation(s)
- Nilda Espinola-Zavaleta
- Echocardiography in Outpatient Clinic, Instituto Nacional de Cardiología Ignacio Chávez, Juan Badiano No. 1, Colonia Sección XVI Tlalpan, 14080 México, D.F., Mexico.
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22
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Pfammatter JP. [Practical management of common arrhythmias in children]. Praxis (Bern 1994) 2005; 94:1765-8. [PMID: 16320891 DOI: 10.1024/0369-8394.94.45.1765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Premature supraventricular or ventricular beats are frequently seen in children of all age groups and are in most instances a benign condition. Intermittent and infrequent premature beats usually are not an indication for a cardiologic work-up. If ventricular or supraventricular premature beats are frequent and persist over a period of weeks or months, we usually recommend a cardiological evaluation. In those patients where ventricular or supraventricular tachycardias are found, the treatment is based on symptomatology, frequency of arrhythmias and impact on quality of life. In ventricular tachycardias, the presence of underlying cardiac disease is of prognostic importance and treatment more aggressive. Idiopathic ventricular tachycardia without structural heart disease usually shows a benign course and has a good prognosis.
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MESH Headings
- Age Factors
- Anti-Arrhythmia Agents/therapeutic use
- Arrhythmias, Cardiac/diagnosis
- Arrhythmias, Cardiac/etiology
- Arrhythmias, Cardiac/therapy
- Cardiac Complexes, Premature/diagnosis
- Cardiac Complexes, Premature/etiology
- Cardiac Complexes, Premature/therapy
- Child
- Child, Preschool
- Electrocardiography
- Electrocardiography, Ambulatory
- Humans
- Infant
- Infant, Newborn
- Prognosis
- Quality of Life
- Risk Factors
- Tachycardia/diagnosis
- Tachycardia/etiology
- Tachycardia/therapy
- Tachycardia, Paroxysmal/diagnosis
- Tachycardia, Supraventricular/diagnosis
- Tachycardia, Supraventricular/etiology
- Tachycardia, Supraventricular/physiopathology
- Tachycardia, Supraventricular/therapy
- Tachycardia, Ventricular/diagnosis
- Tachycardia, Ventricular/etiology
- Tachycardia, Ventricular/therapy
- Time Factors
- Ventricular Premature Complexes/diagnosis
- Ventricular Premature Complexes/etiology
- Ventricular Premature Complexes/physiopathology
- Wolff-Parkinson-White Syndrome/diagnosis
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Affiliation(s)
- J P Pfammatter
- Abteilung Pädiatrische Kardiologie, Medizinische Universitätskinderklinik, Bern.
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23
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Abstract
BACKGROUND There were few reports on the pathological characteristics of the conduction system in myocarditis. This study was aimed to clarify the pathological characteristics of complete atrioventricular (AV) block in myocarditis. METHODS AND RESULTS We studied serial electrocardiograms in experimental myocarditis in mice and also examined their cardiac pathology. After taking baseline electrocardiograms, mice were inoculated intraperitoneally with the encephalomyocarditis virus. Electrocardiograms were serially recorded until day 360. Serial electrocardiograms revealed the appearance of complete AV block. Myocardial lesions were found in the hearts of mice with these ectopic beats. Mononuclear cell infiltrations into the His bundle and necrotic lesions of the conduction system were found in 10.7% (18/168) of mice with complete AV block. However, 17.3% (29/168) of mice showed no evident pathological lesions except the edematous changes of AV node. CONCLUSIONS The appearance of complete AV block in myocarditis may suggest not only significantly comparable pathological lesions of the conduction system but also the trivial edematous changes; in clinical settings, in the former case, permanent pacing therapy is necessary, and in the latter case, the disease may be transient and could be recovered from complete AV block. This study may shed light on the pathological characteristics of complete AV block in myocarditis.
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Affiliation(s)
- Minoru Ohmae
- Kochi General Rehabilitation Hospital, Kochi 781-8130, Japan
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24
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Kim PH, Ahn SJ, Kim JS. Frequency of arrhythmic events during head-up tilt testing in patients with suspected neurocardiogenic syncope or presyncope. Am J Cardiol 2004; 94:1491-5. [PMID: 15589002 DOI: 10.1016/j.amjcard.2004.08.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2004] [Accepted: 08/09/2004] [Indexed: 11/25/2022]
Abstract
Head-up tilt testing (HUT) is a useful diagnostic tool for evaluating suspected neurocardiogenic syncope. Although arrhythmic events during HUT have been occasionally reported, their incidence in a large number of patients is unknown. We aimed to assess the incidence and clinical significance of arrhythmic events in patients with suspected neurocardiogenic syncope who underwent HUT with isoproterenol provocation. For 2,242 patients who underwent HUT, the incidence of total arrhythmic events was 31%: bradyarrhythmias 24%, premature beats 4%, and tachyarrhythmias 3%. For 547 patients who developed bradyarrhythmias during HUT, the incidence of junctional arrhythmias was 92%. For 702 arrhythmic events, the incidence of arrhythmic events during the first phase of HUT was significantly lower than the second phase (p <0.001). The incidence of arrhythmic events in patients with positive HUT responses was significantly higher than in those with negative responses (p <0.001). In patients with positive responses, bradyarrhythmias were noted in 85%, and junctional arrhythmia was the most common arrhythmic event. Of the positive responses, 353 patients (61%) had the vasodepressive type, 181 (32%) patients the mixed type, and the remaining 39 (7%) the cardioinhibitory type. Of 2,242 patients, ventricular fibrillation occurred in 1 patient (0.04%). Thus, bradyarrhythmias were the most common arrhythmic events during HUT with isoproterenol provocation. Serious ventricular tachyarrhythmia rarely occurred.
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Affiliation(s)
- Phil Ho Kim
- Division of Cardiology, Cardiac and Vascular Center, Samsung Medical Center, Department of Internal Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea
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25
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Abstract
BACKGROUND A prolonged QT interval is associated with a risk for life-threatening events. However, little is known about prognostic implications of the reverse-a short QT interval. Several members of 2 different families were referred for syncope, palpitations, and resuscitated cardiac arrest in the presence of a positive family history for sudden cardiac death. Autopsy did not reveal any structural heart disease. All patients had a constantly and uniformly short QT interval at ECG. METHODS AND RESULTS Six patients from both families were submitted to extensive noninvasive and invasive work-up, including serial resting ECGs, echocardiogram, cardiac MRI, exercise testing, Holter ECG, and signal-averaged ECG. Four of 6 patients underwent electrophysiological evaluation including programmed ventricular stimulation. In all subjects, a structural heart disease was excluded. At baseline ECG, all patients exhibited a QT interval <or=280 ms (QTc <or=300 ms). During electrophysiological study, short atrial and ventricular refractory periods were documented in all and increased ventricular vulnerability to fibrillation in 3 of 4 patients. CONCLUSIONS The short QT syndrome is characterized by familial sudden death, short refractory periods, and inducible ventricular fibrillation. It is important to recognize this ECG pattern because it is related to a high risk of sudden death in young, otherwise healthy subjects.
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Affiliation(s)
- Fiorenzo Gaita
- Division of Cardiology, Ospedale Mauriziano Umberto I, Torino, Italy.
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26
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Abstract
METHODS Atrial premature beats are frequently diagnosed during pregnancy, supraventricular tachycardia (atrial tachycardia, AV nodal reentrant tachycardia, circus movement tachycardia) less frequently. For acute therapy, electrical cardioversion with 50-100 J is indicated in all unstable patients. In stable supraventricular tachycardia, initial therapy includes vagal maneuvers to terminate breakthrough tachycardias. For short-term management, when vagal maneuvers fail, intravenous adenosine is the drug of first choice and may safely terminate the arrhythmia. For long-term therapy, beta-blocking agents with beta(1) selectivity are first-line drugs; class Ic agents or the class III drug sotalol represent effective and therapeutic alternatives. Ventricular premature beats are also frequently present during pregnancy and benign in most of the unstable patients; however, malignant ventricular tachyarrhythmias (sustained ventricular tachycardia, ventricular flutter, ventricular fibrillation) are less frequently observed. Electrical cardioversion is necessary in all patients with hemodynamically unstable situation and life-threatening ventricular tachyarrhythmias; in hemodynamically stable patients, initial therapy with ajmaline, procainamide or lidocaine is indicated. If prophylactic therapy is needed, beta-blocking agents with beta(1) selectivity are regarded as drugs of first choice. If this therapy proves ineffective, class Ic agents or sotalol can be considered. In patients with syncopal ventricular tachycardia, ventricular fibrillation, ventricular flutter or aborted sudden death, an implantable cardioverter-defibrillator is indicated. In patients with symptomatic bradycardia, a pacemaker can be implanted using echocardiography at any stage of pregnancy. CONCLUSIONS The treatment of the pregnant patient with cardiac arrhythmias requires important modifications of the standard practice of arrhythmia management. The goal of therapy is to protect the patient and fetus through delivery, after which chronic or definitive therapy can be administered.
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MESH Headings
- Anti-Arrhythmia Agents/adverse effects
- Anti-Arrhythmia Agents/therapeutic use
- Cardiac Complexes, Premature/classification
- Cardiac Complexes, Premature/diagnosis
- Cardiac Complexes, Premature/etiology
- Cardiac Complexes, Premature/therapy
- Electric Countershock
- Electrocardiography, Ambulatory
- Female
- Humans
- Infant, Newborn
- Pregnancy
- Pregnancy Complications, Cardiovascular/classification
- Pregnancy Complications, Cardiovascular/diagnosis
- Pregnancy Complications, Cardiovascular/etiology
- Pregnancy Complications, Cardiovascular/therapy
- Tachycardia, Supraventricular/classification
- Tachycardia, Supraventricular/diagnosis
- Tachycardia, Supraventricular/etiology
- Tachycardia, Supraventricular/therapy
- Tachycardia, Ventricular/classification
- Tachycardia, Ventricular/diagnosis
- Tachycardia, Ventricular/etiology
- Tachycardia, Ventricular/therapy
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Affiliation(s)
- Hans-Joachim Trappe
- Medizinische Klinik II (Schwerpunkte Kardiologie und Angiologie), Universitätsklinik Marienhospital Herne, Ruhr-Universität Bochum
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27
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Al-Ahmad A, Link M, Estes NAM, Wang PJ. Inappropriate shock and pacing? J Cardiovasc Electrophysiol 2003; 14:220-2. [PMID: 12693511 DOI: 10.1046/j.1540-8167.2003.02477.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Amin Al-Ahmad
- New England Cardiac Arrhythmia Center, Division of Cardiology, Department of Medicine, Tufts-New England Medical Center, Boston, Massachusetts 02111, USA
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28
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Klemenkov SV, Razumov AN, Iavisia AM, Voronin SS, Kubushko IV. [Effect of combined application of nitrogen baths and 6 month physical training on physical work capacity and extrasystole in patients with ischemic heart disease and stable stenocardia]. TERAPEVT ARKH 2003; 75:23-6. [PMID: 14959464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
AIM To study effects of combined use of general artificial nitric baths and bicycle exercise for 6 months on physical performance (PP) and extrasystole (ES) in patients with coronary heart disease (CHD) and stable angina pectoris (SAP) of functional class I-II. MATERIAL AND METHODS A total of 129 CHD with SAP patients entered the study. Of them, 44 patients received balneotherapy (a course of general artificial nitric baths); 37 patients took the baths and exercised on bicycle ergometer; 48 patients took the baths, exercised on bicycle ergometer in the outpatient clinic and continued the exercises for 6 months. The patients were examined with spiroveloergometry and ambulatory Holter ECG monitoring. RESULTS The latter group of patients achieved the highest training effect manifesting with increased PP and coronary heart reserve, an antiarrhythmic effect (a 73.3% fall in the mean number of ventricular ES for 24 hours, a 72.2% one in this number of supraventricular ES). CONCLUSION A significant efficacy is shown of combined use of general nitric baths and bicycle exercise with prolongation for 6 months in CHD patients and SAP of functional class I-II with ES.
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29
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Mikhailova SD, Storozhakov GI, Popov MA, Semushkina TM, Bebyakova NA. Effect of thyrotropin-releasing hormone on the development of cardiac arrhythmias during stimulation of sensorimotor cortex in cats. Bull Exp Biol Med 2002; 134:430-1. [PMID: 12802442 DOI: 10.1023/a:1022621810089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Preliminary intravenous injection of thyrotropin-releasing hormone in a dose of 20 g/kg to cats with developing myocardial ischemia during stimulation of the cerebrocortical sensorimotor zone had a pronounced antiarrhythmic effect.
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30
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Komarnicki M, Kaźmierczak M, Woźny T. Ambulatory electrocardiographic evaluation of the heart in patients treated by megachemotherapy and bone marrow transplantation. Haematologia (Budap) 2002; 32:1-10. [PMID: 12243549 DOI: 10.1163/156855902760262709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of the study was evaluation of the frequency of conduction defects and cardiac arrhythmias before and one month (once a week) after bone marrow transplantation (BMT). It was evaluated by 24-hour electrocardiography based on the Holter's method. There were 50 patients (mean age 29.0 years) examined who were treated with megachemotherapy based on BuCy2, BuCy4 (busulphan and cyclophosphamide), BEAM (carmustine, etoposide, cytarabine, melphalan) and dexaBEAM (dexa-dexamethason) programs before BMT. No heart conduction defects occurred. The mean heart rate increased after BMT. Tachycardia (> 100/min) was observed in 92.5-98.1% of patients and bradycardia (< 60/min) in 41.6-68.0% patients. In 6% of patients bradycardia below 40/min occurred. The heart rate was increased in patients who previously used anthracycline antibiotics, had anaemia or fever, and in patients after autologous BMT (p < 0.05). The complex ventricular extrasystoles were detected in 20% of patients before megachemotherapy. They were more frequently observed in patients with hypokalemia (p < 0.05). After therapy these extrasystoles were observed in a total of 24% patients. There was a statistically significant correlation between this kind of extrasystole and age. The extrasystoles developed mainly in young men. In 10% they occurred de novo and also mainly in men. The heart failure (III degrees, IV degrees according to NYHA) occurred in 14% of patients and death caused by heart (or multiorgan) damage in 18%. Older patients and those who had higher mean heart rate during the first month after BMT were dying more frequently (p < 0.05).
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Affiliation(s)
- M Komarnicki
- Department of Oncology, Karol Marcinkowski University of Medical Sciences, Poznań, Poland.
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31
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Abstract
The propensity to develop specific arrhythmias varies between the sexes. Patients with congestive heart failure (CHF) have a high prevalence of ventricular ectopy. However, it is not known if sex related differences exist in the susceptibility to arrhythmias in the setting of CHF. The study population included 159 men and 77 women (mean age 61 +/- 14 years) admitted for decompensated CHF. The severity of atrial and ventricular arrhythmias was assessed by 24-hour Holter monitoring. None of the patients were on parenteral vasoactive therapy during Holter recording. All measures of ventricular ectopy were markedly lower in women compared to men. The mean hourly ventricular pairs (283 +/- 67 vs 106 +/- 30, P = 0.04), mean hourly repetitive ventricular beats (28 +/- 7 vs 10 +/- 3, P = 0.04), and the frequency of ventricular tachycardia episodes per 24 hours (31 +/- 9 vs 7 +/- 3, P = 0.01) were significantly lower in women. After inclusion of clinical variables and drug therapies in a multivariate analysis, the negative relationship between female sex and the frequency of ventricular pairs (P = 0.04), repetitive ventricular beats (P = 0.04), and ventricular tachycardia episodes (P = 0.0005) remained independent. No differences in atrial ectopy between men and woman were found. Complex ventricular ectopy and episodes of ventricular tachycardia are significantly lower in women with CHF. Whether these finding are relevant to female survival advantage in the setting of heartfailure can only be determined by a prospective study. Further understanding of the mechanisms involved in the protection conferred by the patient's sex would advance our understanding about arrhythmias in heart failure.
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Affiliation(s)
- Doron Aronson
- Cardiology Division, RAMBAM Medical Center, Haifa, Israel
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32
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Abstract
The objective of the present study was to directly visualize ectopic activity associated with ischemia-reperfusion and its progression to arrhythmia. To accomplish this goal, we employed a two-dimensional network of neonatal rat cardiomyocytes and a recently developed model of localized ischemia-reperfusion. Washout of the ischemia-like solution resulted in tachyarrhythmic episodes lasting 15-200 s. These episodes were preceded by the appearance of multiple ectopic sources and propagation of ectopic activity along the border of the former ischemic zone. The ectopic sources exhibited a slow rise in diastolic calcium, which disappeared upon return to the original pacing pattern. Border zone propagation of ectopic activity was followed by its escape into the surrounding control network, generating arrhythmias. Together, these observations suggest that upon reperfusion, a distinct layer, which consists of ectopically active, poorly coupled cells, is formed transiently over an injured area. Despite being neighbored by a conductive and excitable tissue, this transient functional layer is capable of sustaining autonomous waves and serving as a special conductive medium through which ectopic activity can propagate before spreading into the surrounding healthy tissue.
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Affiliation(s)
- Ara Arutunyan
- Department of Physiology, Health Sciences Center, Texas Tech University, 3601 Fourth Street, Lubbock, TX 79430, USA
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33
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Turcu A, Berthet F, Lévêque L, Besancenot JF. [Complete dysphagia during paroxysmal atrial fibrillation]. Presse Med 2002; 31:935. [PMID: 12148140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
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34
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Morady F. Widening of the QRS complex during atrial pacing: what is the mechanism? J Cardiovasc Electrophysiol 2002; 13:627-8. [PMID: 12108511 DOI: 10.1046/j.1540-8167.2002.00627.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Fred Morady
- Department of Internal Medicine, University of Michigan, Ann Arbor 48109-0022, USA.
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35
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Abstract
BACKGROUND Primary catheter ablation of atrial fibrillation is a new and curative option for the treatment of patients with drug-refractory atrial fibrillation. It is aiming at a long-term restoration of sinus rhythm and thereby causing a coordinated atrial contraction. ABLATION METHODS Two different ablation strategies have been established: The "trigger elimination" tries to identify triggering atrial extrasystoles (mostly within the pulmonary veins), followed by focal ablation or isolation within the pulmonary veins. The "substrate modification" changes by long linear radiofrequency-induced lesions the ability of the atrial myocardium to sustain atrial fibrillation. VALUATION Both treatment options still have to prove their effectiveness in carefully monitored follow-up, before they can be offered to the general patient population with atrial fibrillation.
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36
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Ashikaga T, Nishizaki M, Arita M, Yamawake N, Fujii H, Kishi Y, Isobe M, Hiraoka M. Opening of K(ATP) channel attenuates the increase in QT dispersion produced by the first balloon inflation during coronary angioplasty. Circ J 2002; 66:469-72. [PMID: 12030342 DOI: 10.1253/circj.66.469] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Increased QT dispersion predicts the occurrence of lethal ventricular arrhythmias complicating percutaneous transluminal coronary angioplasty (PTCA). Moreover, these arrhythmias occur more frequently at the first balloon inflation. Activation of the K(ATP) channel may influence QT dispersion and ventricular arrhythmias during coronary angioplasty, so 40 consecutive patients with stable angina were randomized to receive 3 mg/h of nicorandil infusion or placebo and QT dispersion and the incidence of ventricular ectopy were investigated before and throughout PTCA. There were no significant differences in QT dispersion at baseline between the nicorandil group (42+/-8 ms) and placebo (42+/-12ms). At the first balloon inflation, the QT dispersion in the nicorandil group (51+/-13 ms) was significantly less than that observed with placebo (76+/-16ms, p<0.001). However, the QT dispersion at the second inflation was similar in both groups (nicorandil: 45+/-12ms; placebo: 52+/-14ms). Ventricular ectopy was observed in 1 patient receiving nicorandil and 5 patients in the placebo group during the first inflation, and none in the nicorandil and 1 patient in the placebo group during the second balloon inflation. Activation of the K(ATP) channel may inhibit the development of ventricular arrhythmias during PTCA, particularly at the first balloon inflation.
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Affiliation(s)
- Takashi Ashikaga
- Department of Cardiology, Yokohama Minami Kyosai Hospital, Kanagawa, Japan.
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37
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Manz M, Susilo R. [Electrolytes in cardiac arrhythmias. Especially effective in coronary heart disease patients]. MMW Fortschr Med 2002; 144:48. [PMID: 11928266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Affiliation(s)
- M Manz
- GmbH & Co.KG, Abt. Forschung & Entwicklung, D-52475 Alsdorf
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38
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Barwitz HJK. [Cardiac arrhythmias in advanced age. That could be a thyrotoxic crisis!]. MMW Fortschr Med 2002; 144:38-40. [PMID: 11883046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Affiliation(s)
- Harald J K Barwitz
- Lehrbeauftragter für Allgemeinmedizin der Ludwig-Maximilians-Universität München.
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39
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40
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Hancock EW. Aberrant conduction or ectopic beats? Hosp Pract (1995) 2001; 36:13-4. [PMID: 11446595 DOI: 10.1080/21548331.2001.11444122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- E W Hancock
- Emeritus, Stanford University School of Medicine, Calif, USA
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41
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Kujaník S, Snincák M, Galajdová K, Racková K. Cardiovascular changes during sudden ascent in a cable cabin to the moderate altitude. Physiol Res 2001; 49:729-31. [PMID: 11252541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Our aim was to test the hypothesis that the occurrence of extrasystoles in higher decennia is proportional to the altitude. The occurrence of supraventricular (SVPB) and ventricular (VEB) extrasystoles, values of systolic and diastolic blood pressure and the heart rate were studied in 20 healthy elderly men (50-64 years) during cable cabin transportation to a moderate altitude. These values were measured in stations located at 898 m, 1764 m, and 2632 m above sea level during the transportation in both directions. Our records show that the values of blood pressure and heart rate were within normal limits during the whole period of transportation. Both SVPB and VEB were increasing during the ascent and decreasing to the initial values during the descent compared to the values at altitude of 898 m. The highest values (6 to 7-times exceeding the initial ones) were measured at the summit. The results have demonstrated that the occurrence of SVPB and VEB is proportional to the altitude. The increased incidence in the number of extrasystoles is suggested to be mediated by beta-adrenoceptors.
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Affiliation(s)
- S Kujaník
- Department of Physiology, Faculty of Medicine, Safárik University, Kosice, Slovak Republic
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42
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Magadle R, Weiner P, Sozkover A, Berar-Yanay N. Recurrent deglutition syncope. Isr Med Assoc J 2001; 3:222-3. [PMID: 11303383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Affiliation(s)
- R Magadle
- Department of Medicine A, Hillel Yaffe Medical Center, Hadera, Israel.
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43
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Poza JJ, López de Munain A, García-Bragado F, Martí-Massó JF. [Andersen syndrome. Description of a case] . Neurologia 2000; 15:366-9. [PMID: 11143505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
A 17 year-old man, with periodic muscular weakness since the age of 6 years, is presented. The episodes of periodic paralysis were of variable duration, from 1 to 3 days, and were induced by physical exercise or by stress. Weakness was generalised, although predominant in anterior compartment of the legs, with foot drop. Interictal neurological examination was absolutely normal. He showed dysmorphic features, with micrognatia. Cardiac examination revealed continuous arrhythmia. Basal EKG and 24 hours EKG-Holter confirmed the existence of abundant ventricular extrasystoles, with episodes of ventricular tachycardia, without clinical manifestations. Echocardiogram was normal. Ictal and interictal ENG-EMG, and muscle and nerve biopsies were normal. Serum potassium levels during the episodes ranged from 3 to 3.6 mEq/l (N: 3.5-4.5 mEq/l), being normal interictally (4-5 mEq/l). Oral administration of potassium did not prevent the development of episodic weakness. He had no familial history of similar symptoms. This association of periodic paralysis, cardiac arrhythmia and dysmorphic features correspond to a rare entity named Andersen's syndrome.
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Affiliation(s)
- J J Poza
- Servicio de Neurología, Hospital Aránzazu, San Sebastián.
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Ijiri H, Kohno I, Yin D, Iwasaki H, Takusagawa M, Iida T, Osada M, Umetani K, Ishihara T, Sawanobori T, Ishii H, Komori S, Tamura K. Cardiac arrhythmias and left ventricular hypertrophy in dipper and nondipper patients with essential hypertension. Jpn Circ J 2000; 64:499-504. [PMID: 10929777 DOI: 10.1253/jcj.64.499] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To evaluate the behavior of cardiac arrhythmias in dipper and nondipper hypertensive patients, 48-h ambulatory blood pressure monitoring, 24-h Holter electrocardiogram recording and echocardiographic studies were performed in 56 untreated outpatients with essential hypertension. These patients were divided into 2 groups according to the presence (dipper, n=33) or absence (nondipper, n=23) of reduction of both systolic and diastolic blood pressure during nighttime by an average of more than 10% of daytime blood pressure. Mean 48-h systolic and diastolic blood pressures did not differ between the 2 groups. Nondipper patients had a significantly larger left atrial dimension (31.9+/-3.8 vs 35.6+/-3.7 mm; p<0.01), left ventricular mass index (114+/-26 vs 136+/-36 g/m2; p<0.05), as well as a larger number of total supraventricular (16+/-19 vs 89+/-197 beats; p<0.05) and ventricular ectopic beats (7+/-14 vs 47+/-96 beats; p<0.05) during daytime as compared with dippers. In conclusion, nondipper hypertensive patients are likely to experience supraventricular and ventricular arrhythmias more frequently than dippers. A blunted nocturnal blood pressure fall may be involved in the appearance of cardiac arrhythmias in patients with essential hypertension.
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Affiliation(s)
- H Ijiri
- Second Department of Medicine, Yamanashi Medical University, Nakakoma, Japan.
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45
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Borchard U, Hafner D. [Ion channels and arrhythmias]. Z Kardiol 2000; 89 Suppl 3:6-12. [PMID: 10810780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Changes in ionic currents through ion channels of the myocardial cell membrane have to be regarded as main cause of cardiac arrhythmias. Three basic arrhythmogenic mechanisms are responsible for the initiation of tachyarrhythmias: 1. The disturbance of normal automaticity in cardiac pacemaker cells dependent on the currents If, ICa-L, ICa-T or IK-ACh,Ado and the occurrence of abnormal automaticity in atrial and ventricular working myocardium based on the currents ICa-L, INa, IK, IK1 or IK-ACh,Ado. 2. Triggered activity which may be recognized by the appearance of early (EAD) or late afterdepolarizations (LAD). EAD are mainly due to inhibition of the outward currents IKr and IKs and are favoured by an increase in the inward currents INa and ICa-L, respectively. Typical arrhythmias are torsade de pointes occurring during treatment with K(+)-channel inhibitors (e.g. sotalol) or in patients with QT-syndrome. LAD may be observed during Ca(2+)-overload of the myocardial cell (digitalis intoxication, catecholamines) and are based on the transient inward current Iti, which is build up by the participation of the currents INa/Ca, INS and ICa-L. 3. Reentry mechanisms are the most frequent cause of tachyarrhythmias. They originate in an anatomically defined excitation circle with unidirectional block. Na(+)- and Ca(2+)-channel dependent disturbances of conduction with long excitable gap may be distinguished from Na(+)-channel dependent disturbances of conduction and refractory period with short excitable gap. Interruption of reentry is possible in the first case by depression of conduction and excitability (Na(+)- or Ca(2+)-channel blockers), in the second case by increase in refractory period (K(+)- or Na(+)-channel blockers).
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Affiliation(s)
- U Borchard
- Heinrich-Heine-Universität Düsseldorf, Institut für Pharmakologie, Düsseldorf
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Okishige K, Ohkubo T, Goseki Y, Matsubara T, Hiejima K, Ibukiyama C. Experimental study of the effects of multi-site sequential ventricular pacing on the prophylaxis of ventricular fibrillation. Jpn Heart J 2000; 41:193-204. [PMID: 10850535 DOI: 10.1536/jhj.41.193] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Previous studies report a significant prophylactic effect on the occurrence of atrial fibrillation by simultaneous multi-site atrial pacing. We investigated the effects of multi-site sequential ventricular pacing (MSVP), which may be preferable to simultaneous multi-site pacing in terms of the prophylaxis of the occurrence of ventricular fibrillation (VF). Needle electrodes were inserted at ten different epicardial sites on both ventricles for MSVP in 12 adult beagle dogs. Four premature ventricular extrastimuli (PVE) were introduced to provoke VF reproducibly from a separate electrode in the left ventricle. The 4 PVE were applied to try to provoke VF during MSVP in a comparable fashion to the activation sequence during sinus rhythm. We compared the prophylactic effects of MSVP on the inducibility of VF by changing the number of stimulation sites to either 1, 3, 5, or 10 epicardial sites. We performed a total of 363 trials of induction and suppression of VF. The occurrence rates of VF by the 4 PVE for the various number of epicardial stimulation sites of MSVP, i.e., at 1, 3, 5, and 10 sites, were 0.8263, 0.4286, 0.4450, and 0.2857, respectively (p < 0.05). There was a significant prophylactic effect of MSVP on the inducibility of VF, and this effect became stronger as the number of MSVP sites was increased from 3 to 10. The hemodynamic state was relatively stable during MSVP. MSVP seems to be a promising method with which to reduce the occurrence of VF, and a larger number of stimulation sites would be more effective in terms of the prophylaxis of VF.
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Affiliation(s)
- K Okishige
- Cardiovascular Department, Yokohama Red Cross Hospital, Japan
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Zanetti G, Ostini F, Montanari E, Russo R, Elena A, Trinchieri A, Pisani E. Cardiac dysrhythmias induced by extracorporeal shockwave lithotripsy. J Endourol 1999; 13:409-12. [PMID: 10479005 DOI: 10.1089/end.1999.13.409] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PATIENTS AND METHODS We evaluated in 269 consecutive patients the incidence and gravity of dysrhythmic complications during nonsynchronized extracorporeal shockwave lithotripsy (SWL) using an electromagnetic lithotripter. RESULTS Dysrhythmia occurred during treatment in 22 patients (8.8%) with no previous cardiac dysrhythmia. Ventricular extrasystoles occurred in 14 patients, atrial extrasystoles in 7 patients, and sinus bradycardia in 1 patient. It was not necessary to terminate treatment because of the occurrence of dysrhythmia in any of the patients. For 13 of the 22 patients (59%), it was sufficient to interrupt the treatment momentarily to obtain resumption of the normal rhythm. For 8 patients (36%), treatment was continued after triggering the release of the shockwaves with the refractory phase of the heart cycle. For one case of bradycardia (42 beats/min), it was possible to continue with the treatment after intravenous administration of atropine 0.5 mg. Pretreatment dysrhythmias were revealed by the electrocardiographic examination in 16 of the patients studied (6.3%). CONCLUSIONS Extracorporeal shockwave lithotripsy without ECG triggering has been found to be fast and efficient and not correlated with the occurrence of dysrhythmic episodes of any particular clinical significance. No significant correlation was found between the occurrence of dysrhythmia, the side treated, the number and strength of the shockwaves, or the administration of analgesics. It was found, however, that dysrhythmia occurred almost exclusively in treatments involving the kidneys. The ECG-triggering option was indispensable in some patients in order to complete the lithotripsy without complications.
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Affiliation(s)
- G Zanetti
- Institute of Urology, I.R.C.C.S. Ospedale Maggiore di Milano, Milan, Italy.
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Abstract
A patient with marked first-degree AV block and a DDDR pacemaker presented with a history of paroxysmal narrow QRS tachycardia, subsequently identified as sinus tachycardia (with a very long PR interval), causing a clinical problem similar to pacemaker syndrome because of loss of AV synchrony. The latter resulted from an excessively long postventricular atrial refractory period (PVARP) that prevented sensing of sinus P waves. The unfavorable hemodynamics caused reflex sinus tachycardia. The long PVARP was mandated by the mode switching algorithm of this particular device and was automatically set according to the selected tachycardia detection rate. The patient became asymptomatic when the mode switching function was turned off and the PVARP shortened.
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Affiliation(s)
- P Jaïs
- Hôpital Cardiologique du Haut Lévêque, Bordeaux Pessac, France
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Alexiou K, Dschietzig T, Simsch O, Laule M, Hundertmark J, Baumann G, Stangl K. Arrhythmogenic effects induced by coronary conversion of pulmonary big endothelin to endothelin: aggravation of this phenomenon in heritable hyperlipidemia. J Am Coll Cardiol 1998; 32:1773-8. [PMID: 9822108 DOI: 10.1016/s0735-1097(98)00440-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES We investigated whether endogenous pulmonary big endothelin has arrhythmogenic properties under normal conditions and in heritable hyperlipidemia. BACKGROUND Endothelin (ET), one of the most potent vasoconstrictors, is known to induce ventricular arrhythmias. It is unclear, however, whether its precursor, big endothelin, released from the lung, contributes to arrhythmogenesis. METHODS In a lung-heart model in which a Langendorff heart is serially perfused with the effluent from the isolated lung of the same animal, we evaluated arrhythmias in control and in Watanabe heritable hyperlipidemic (WHHL) rabbits. RESULTS In both controls (n=12) and WHHL (n=8), serial perfusion evoked a decrease in coronary flow (controls, -11+/-3%; WHHL, -25+/-6%) and a fourfold increase of ventricular extrasystoles (VES) (controls, 40.7+/-8; WHHL, 40.2+/-5 VES/40 min, p < 0.05). However, WHHL developed more and longer nonsustained ventricular tachycardias (VT) compared with controls (incidence, 1.38+/-1.1 vs. 0.33+/-0.5 VT/40 min, p < 0.05; length, 14.36+/-3.1 vs. 7.25+/-1.5 beats/VT, p < 0.05). Arrhythmias were not ischemia-induced because corresponding mechanical flow reduction had no arrhythmogenic effect (n=6 in controls and WHHL). Although vasoconstriction disappeared entirely, arrhythmias were only partly suppressed by ET(A) antagonists (BQ-123, 2 micromol/liter; A-127722, 20 micromol/liter). The ET-converting enzyme inhibitor phosphoramidon (50 micromol/liter) completely suppressed arrhythmias and vasoconstriction. The ET(B) antagonists (IRL-1038, 4 micromol/liter; IRL-1025, 5 micromol/liter) had no effect (n=6). CONCLUSIONS Endogenous pulmonary big ET produces arrhythmogenic effects that are aggravated in heritable hyperlipidemia. These effects, requiring coronary conversion of big ET into ET, are partly ET(A)-mediated and ET(B)-independent.
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Affiliation(s)
- K Alexiou
- Medizinische Klinik und Poliklinik I, Charité, Humboldt-Universität zu Berlin, Germany
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Roegel JC, Yannoulis N, De Jong W, Feldman J, Bousquet P. Preventive effect of rilmenidine on the occurrence of neurogenic ventricular arrhythmias in rabbits. J Hypertens Suppl 1998; 16:S39-43. [PMID: 9747909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Centrally acting antihypertensive drugs bearing an imidazoline or a related chemical structure inhibit sympathetic nervous output to the heart and vascular beds, and enhance parasympathetic tone. Cardiac ischaemia and ventricular arrhythmias that can result from hypertension are likely to benefit from such effects. OBJECTIVE To investigate the effects of rilmenidine, an oxazoline with antihypertensive properties, in a model of neurogenically induced ischaemic ventricular arrhythmias. METHODS AND RESULTS Bicuculline, a alpha-aminobutyric acid (GABA(A)) receptor antagonist, was administered intracisternally in pentobarbitone anaesthetized rabbits; 10 microg/kg intracisternal bicuculline induced polymorphic ventricular ectopic beats and ventricular tachycardia, while blood pressure increased by about 50-60% and heart rate in sinus rhythm decreased by about 20%. Rilmenidine pretreatment (10 min), either administered intravenously (0.01, 0.1, 1 mg/kg) or intracisternally (3, 10, 30 microg/kg), dose-dependently prevented the occurrence of bicuculline-induced arrhythmias and, because of a lower baseline, the blood pressure values reached were less when compared with controls. Intracisternal idazoxan (15 microg/kg) had no significant antiarrhythmic effect but antagonized, in part, the haemodynamic and antiarrhythmic effects of rilmenidine (1 mg/kg intravenously; 30 microg/kg intracisternally). CONCLUSION The antiarrhythmic effects observed with rilmenidine are mainly mediated by blunting the bicuculline-induced increase in the sympathetic nervous output to the heart and the vascular beds. These effects of rilmenidine are likely to originate from action on the central as well as on the peripheral nervous systems. Direct coronary or cardiac effects might also play a role, in particular at low non-hypotensive intravenous doses.
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Affiliation(s)
- J C Roegel
- Laboratoire de Pharmacologie Cardiovasculaire et Rénale, CNRS ERS 109, Faculté de Médecine, Strasbourg, France
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