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Atrioventricular Block (atrioventricular + block)
Kinds of Atrioventricular Block Selected AbstractsHypersensitivity Myocarditis Presenting as Atrioventricular Block and Wide Complex Tachycardia in a ToddlerCONGENITAL HEART DISEASE, Issue 5 2008Neil Bhogal MD ABSTRACT A 13-month-old boy presented with acute onset of complete atrioventricular block and wide complex tachycardia but normal hemodynamics. Endomyocardial biopsy disclosed active myocarditis with eosinophils, suggesting a hypersensitivity reaction. With no treatment, the rhythm disturbance resolved within days of onset. Our patient's presentation and self-limited illness is unique. To our knowledge, this is only the second reported case of eosinophilic myocarditis in a young child or infant. [source] Paroxysmal High-Grade Atrioventricular Block and Syncope in a Previously Healthy Child: What is the Mechanism?JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2010RONALD J. KANTER M.D. No abstract is available for this article. [source] Spontaneous Transition of 2:1 Atrioventricular Block to 1:1 Atrioventricular Conduction During Atrioventricular Nodal Reentrant Tachycardia:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2003Evidence Supporting the Intra-Hisian or Infra-Hisian Area as the Site of Block Introduction: The incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction during AV nodal reentrant tachycardia has not been well reported. Among previous studies, controversy also existed about the site of the 2:1 AV block during AV nodal reentrant tachycardia. Methods and Results: In patients with 2:1 AV block during AV nodal reentrant tachycardia, the incidence of spontaneous transition of 2:1 AV block to 1:1 AV conduction and change of electrophysiologic properties during spontaneous transition were analyzed. Among the 20 patients with 2:1 AV block during AV nodal reentrant tachycardia, a His-bundle potential was absent in blocked beats during 2:1 AV block in 8 patients, and the maximal amplitude of the His-bundle potential in the blocked beats was the same as that in the conducted beats in 4 patients and was significantly smaller than that in the conducted beats in 8 patients (0.49 ± 0.25 mV vs 0.16 ± 0.07 mV, P = 0.007). Spontaneous transition of 2:1 AV block to 1:1 AV conduction occurred in 15 (75%) of 20 patients with 2:1 AV block during AV nodal reentrant tachycardia. Spontaneous transition of 2:1 AV block to 1:1 AV conduction was associated with transient right and/or left bundle branch block. The 1:1 AV conduction with transient bundle branch block was associated with significant His-ventricular (HV) interval prolongation (66 ± 19 ms) compared with 2:1 AV block (44 ± 6 ms, P < 0.01) and 1:1 AV conduction without bundle branch block (43 ± 6 ms, P < 0.01). Conclusion: The 2:1 AV block during AV nodal reentrant tachycardia is functional; the level of block is demonstrated to be within or below the His bundle in a majority of patients with 2:1 AV block during AV nodal reentrant tachycardia, and a minority are possibly high in the junction between the AV node and His bundle. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1337-1341, December 2003) [source] Evaluation of Myocardial Performance with Conventional Single-Site Ventricular Pacing and Biventricular Pacing in a Canine Model of Atrioventricular BlockJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2003PATRICIO A. FRIAS M.D. Introduction: The aim of this study was to evaluate epicardial biventricular pacing as a means of maintaining synchronous ventricular activation in an acute canine model of AV block with normal ventricular anatomy and function. Chronic single-site ventricular pacing results in dyssynchronous ventricular activation and may contribute to ventricular dysfunction. Biventricular pacing has been used successfully in adult patients with congestive heart failure. Methods and Results: This was an acute study of open chest mongrel dogs (n = 13). ECG, left ventricular (LV), aortic, and pulmonary arterial pressures were measured. LV impedance catheters were used to assess cardiodynamics using instantaneous LV pressure-volume relations (PVR). Following radiofrequency ablation of the AV node, a temporary pacemaker was programmed 10 beats/min above the intrinsic atrial rate, with an AV interval similar to the baseline intrinsic PR interval. The pacing protocol consisted of 5-minute intervals with the following lead configurations: right atrium-right ventricular apex (RA-RVA), RA-LV apex (LVA), and RA-biventricular using combinations of four ventricular sites (RVA, RV outflow tract [RVOT], LVA, LV base [LVB]). RA-RVA was used as the experimental control. LV systolic mechanics, as measured by the slope of the end-systolic (Ees) PVR (ESPVR, mmHg/cc), was statistically greater (P < 0.05) with all modes of biventricular pacing (RA-RVA/LVA 20.0 ± 2.9, RA-RVA/LVB 18.4 ± 2.9, RA-RVOT/LVA 15.1 ± 1.8, RA-RVOT/LVB 17.6 ± 2.9) compared to single-site ventricular pacing (RA-RVA 12.8 ± 1.6). Concurrent with this improvement in myocardial performance was a shortening of the QRS duration (RA-RVA 97.7 ± 2.9 vs RA-RVA/LVA 75.7 ± 4.9, RA-RVA/LVB 70.3 ± 4.9, RA-RVOT/LVA 65.3 ± 4.4, and RA-RVOT/LVB 76.7 ± 5.9, P < 0.05). Conclusion: In this acute canine model of AV block, QRS duration shortened and LV performance improved with epicardial biventricular pacing compared to standard single-site ventricular pacing. (J Cardiovasc Electrophysiol, Vol. 14, pp. 996-1000, September 2003) [source] Supraventricular Tachycardia with 2:1 Atrioventricular Block:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2000What is the Mechanism? [source] Aortic Dissection and Third-Degree Atrioventricular Block in a Patient With a Hypertensive CrisisJOURNAL OF CLINICAL HYPERTENSION, Issue 1 2008Nikolaos Lionakis MD A 55-year-old man with a history of uncontrolled hypertension was admitted because of an episode of severely elevated blood pressure. An electrocardiogram revealed complete atrioventricular block while imaging showed a dissecting aneurysm of the descending thoracic and abdominal aorta, type B according to the Stanford classification. Laboratory tests revealed significant increases in serum C-reactive protein. Coronary arteriography was performed and was negative for coronary artery disease. A VDD pacemaker was placed, and a combination of 4 antihypertensive agents was used as treatment. Type B aortic dissection may present with a wide range of manifestations. The authors suggest that measurement of C-reactive protein may be used in hypertensive patients to help reflect vascular injury and its degree, progression, and prognosis. Disorders of intraventricular conductivity are rarely seen in both types of dissection of the aorta (type A, B). Atrioventricular conductivity disorders that result in complete atrioventricular block have been reported only in patients with type A dissection (before the bifurcation of the subclavian artery). In this particular case, however, the authors diagnosed an atrioventricular conductivity disorder causing atrioventricular block in a patient with type B dissection. Consequently, the authors speculate that myocardial fibrosis, as a result of long-standing hypertension, could be the main pathogenetic mechanism leading to the development of such phenomena, resulting from a potential expanding of the fibrotic process to the atrioventricular conduction system. [source] Third-Degree Atrioventricular Block in 21 Cats (1997,2004)JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2006H.B. Kellum The effect of 3rd-degree atrioventricular block on long-term outcome in cats is unknown. Clinical findings and long-term outcome of 21 cats with 3rd-degree atrioventricular block were studied retrospectively. Median age of cats studied was 14 years (range 7,19 years). Presenting signs included respiratory distress or collapse, but 6 cats had no clinical signs of disease. Eight cats had congestive heart failure (CHF) at the time that 3rd-degree atrioventricular block was detected. Heart rates ranged from 80 to 140 beats per minute (bpm; median 120 bpm) with no difference in heart rate between cats with and those without CHF. Eleven of 18 cats that had echocardiograms had structural cardiac disease, and 6 cats had cardiac changes consistent with concurrent systemic disease. No atrioventricular nodal lesions were detected by echocardiography. One cat had atrioventricular nodal lesions detected on histologic examination. Median survival of 14 cats that died or were euthanized was 386 days (range 1,2,013 days). Survival did not differ between cats with or without CHF or between cats with or without structural cardiac disease. Thirteen cats with 3rd-degree atrioventricular block survived >1 year after diagnosis, regardless of presenting signs or underlying cardiac disease. Third-degree heart block in cats is often not immediately life threatening. Survival was not affected by the presence of underlying heart disease or congestive heart failure at the time of presentation. Even cats with collapse might survive >1 year without pacemaker implantation. [source] Congenital Complete Atrioventricular BlockPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2001RICHARD A. FRIEDMAN First page of article [source] The Chicago School of Electrocardiography and Second-Degree Atrioventricular Block: An Historical PerspectivePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2001S. SERGE BAROLD First page of article [source] Location and Clinical Implications of High-Degree Atrioventricular Block During Dipyridamole Infusion: A Case ReportANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2002Mazen Alakhras M.D. We describe a patient with bifascicular block, who developed transient high-degree atrioventricular block during dipyridamole infusion. This patient was subsequently found to have significant His-Purkinje disease at electrophysiology study, and underwent permanent pacemaker implantation. Spontaneous atrioventricular block was documented during follow-up. This case report raises the issue of dipyridamole safety in patients with intraventricular conduction defects, and contributes an additional mechanism to the possible explanation of dipyridamole-induced atrioventricular block. A.N.E. 2002;7(2):174,176 [source] Woldemar Mobitz: Early Twentieth Century Expert on Atrioventricular BlockCLINICAL CARDIOLOGY, Issue 11 2009Charles B. Upshaw Jr. MD No abstract is available for this article. [source] Does Aortic Root Enlargement Impair the Outcome of Patients With Small Aortic Root?JOURNAL OF CARDIAC SURGERY, Issue 5 2006Hasan Ardal The aim of this study was to evaluate long-term results of the posterior root enlargement. Methods: Between 1985 and 2002, 124 patients underwent aortic valve replacement with a posterior root enlargement. The main indication was a small aortic valve orifice area to patient body surface area (indexed valve area < 0.85 cm2/m2). Fifty-four (44%) patients were male, and 70 (56%) were female with a mean age 39.1 ± 14.3 years. Indications for operation were severe calcified aortic valve stenosis (37.1%), severe aortic insufficiency (25.8%), or combination (37.1%). Seventy-five (60%) patients received double-valve replacement. A pericardial patch was used in 100 patients (80.6%) and a Dacron patch was used in 24 patients. Results: Operative mortality was 6.4% (8 patients). The causes of hospital mortality were low cardiac output syndrome (LCOS) (in 6 patients), cerebrovascular events (in 1 patient) and multiple organ failure (in 1 patient). Multivariate analysis demonstrated concomitant coronary revascularization to be a significant (p = 0.03) predictor for early mortality. There were six (5.4%) late deaths. Cox proportional hazards regression analysis demonstrated LCOS (p = 0.013) and infective endocarditis (p = 0.003) to be significant predictors for late mortality. Atrioventricular block required a permanent pacemaker was observed in 4 patients (3.2%). Conclusions: Posterior aortic root enlargement techniques can be easily applied without additional risks. Long-term survival and freedoms from valve-related complications are satisfactory. [source] Hypersensitivity Myocarditis Presenting as Atrioventricular Block and Wide Complex Tachycardia in a ToddlerCONGENITAL HEART DISEASE, Issue 5 2008Neil Bhogal MD ABSTRACT A 13-month-old boy presented with acute onset of complete atrioventricular block and wide complex tachycardia but normal hemodynamics. Endomyocardial biopsy disclosed active myocarditis with eosinophils, suggesting a hypersensitivity reaction. With no treatment, the rhythm disturbance resolved within days of onset. Our patient's presentation and self-limited illness is unique. To our knowledge, this is only the second reported case of eosinophilic myocarditis in a young child or infant. [source] Necrotizing Vasculitis: A Cause of Aortic Insufficiency and Conduction System DisturbanceECHOCARDIOGRAPHY, Issue 7 2003Miquel Gómez Pérez M.D. Cardiac involvement in vasculitis syndromes is uncommon. We describe a 50-year-old male who presented with progressive dyspnea and myalgies. Echocardiogram revealed significant thickening of aortic root, aortic cusps, and anterior mitral valve leaflet, with severe aortic regurgitation that required aortic valve replacement. Furthermore, this patient suffered progressive atrioventricular block that needed implantation of a pacemaker. The study performed disclosed the presence of necrotizing vasculitis positive for perinuclear antineutrophil cytoplasmic antibody. (ECHOCARDIOGRAPHY, Volume 20, October 2003) [source] Bradycardia and sinus arrest during percutaneous ethanol injection therapy for hepatocellular carcinomaEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 3 2004A. Ferlitsch Abstract Background, Percutaneous ethanol injection (PEI) is an established method in the treatment of hepatocellular carcinoma (HCC) and considered a safe procedure, with severe complications occurring rarely. Cardiac arrhythmias have not been reported to date. Aim of the study was to investigate the occurrence of dysrhythmias during PEI. Patients and methods, Twenty-six consecutive patients with inoperable HCC were included. During ultrasound-guided PEI with 95% ethanol, electrocardiogram (ECG) monitoring was performed before starting and continuously during PEI. Results, During PEI a significant reduction in mean heart rate (> 20%) was seen in 15 of 26 (58%) patients. In 11 of 26 patients (42%) occurrence of sinuatrial block (SAB) or atrioventricular block (AVB) was observed after a median time of 9 s (range 4,50) from the start of PEI with a median length of 24 s (range 12,480). Clinical symptoms were seen in two patients, including episodes of unconsciousness, seizure-like symptoms in both and a respiratory arrest during PEI in one patient, requiring mechanical ventilation. In four of 12 patients with repeat interventions, dysrhythmias were reproducible during monthly performed procedures. There was a significant association between the occurrence of SAB or AVB and the amount of instilled alcohol (P = 0·03) and post-PEI serum ethanol levels (P = 0·03). Conclusions, Bradycardia and block formation occur frequently during PEI. These symptoms could be explained by a vasovagal reaction and/or the direct effect of ethanol on the sinus node or the right atrial conduction system. Ethanol dose is an important factor for the occurrence of SAB/AVB. ECG-monitoring seems mandatory during PEI. Prophylactic use of intravenously administered Atropine might be useful. [source] Second-degree atrioventricular block (Mobitz Type I) in an adolescent with anorexia nervosa: Intrinsic or acquired conduction abnormalityINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 6 2009Nuray Ö. Kanbur MD Abstract Anorexia nervosa (AN) can cause both functional and structural cardiac complications, including a variety of different conduction abnormalities. This is the first case report of symptomatic diurnal second-degree atrioventricular (AV) block (Mobitz Type I) in an adolescent with AN. We present a 12-year-old girl with AN, restrictor sub-type who reported cardiac symptoms during weight gain, at the time of the initial diagnosis of AV block. Second-degree AV block (Mobitz Type I) is discussed as a possible complication of the AN, as well as being an intrinsic conduction system disease. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2009 [source] Trends and Outcomes in the Hospitalization of Older Americans for Cardiac Conduction Disorders or Arrhythmias, 1991,1998JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2001William B. Baine MD OBJECTIVE: To identify epidemiological trends and measure outcomes in elderly patients hospitalized for cardiac conduction disorders or arrhythmias. DESIGN: Review of the standard 5% samples of the Medicare Provider Analysis and Review Files to characterize 144,512 discharges from 1991 through 1998 in which the principal diagnosis was a conduction disorder or arrhythmia, using the corresponding Enrollment Databases for denominator data. SETTING: Short-stay hospitals in the United States. PARTICIPANTS: Medicare beneficiaries age 65 and older in the standard 5% sample. MEASUREMENTS: Diagnosis-specific trends and rates; discharges by year; cumulative age-, race-, and sex-specific discharge rates; mean length of stay in hospital and in intensive care; mean Medicare reimbursement to the hospital; case-fatality rate in hospital; discharge destinations of patients discharged alive. RESULTS: Annual hospitalizations for sinoatrial node dysfunction, atrial flutter, atrial fibrillation, or ventricular fibrillation increased more rapidly than did the elderly Medicare beneficiary population. Hospitalizations with a principal diagnosis of ventricular extrasystoles or asystole showed steep secular declines. Discharge rates for sinoatrial node dysfunction, a group of rhythms with a nonsinus pacemaker, atrial fibrillation, Mobitz I, or complete atrioventricular block all increased steeply and continuously with patient age. In contrast, discharge rates for atrial flutter or ventricular tachycardia or fibrillation peaked among 75- to 84-year-old patients. White men were at uniquely high risk of hospitalization for atrial flutter or ventricular tachycardia or fibrillation, and, among the white majority, men had higher discharge rates than women for nine of the 11 commonest rubrics. Whites, particularly white women, had the highest discharge rates for atrial fibrillation. Blacks, especially black women, were at disproportionate risk for hospitalization for the group of nonsinus pacemaker rhythms. Diagnosis-specific mean resource costs were strongly correlated with each other and with mean Medicare reimbursement but not with case-fatality rate. CONCLUSION: Medicare claims data demonstrated striking differences among and within diagnoses of heart blocks or arrhythmias in terms of the populations at greatest risk for hospitalization. This variation should be explored further to generate and test hypotheses about differential causation or delivery of care. J Am Geriatr Soc 49:763,770, 2001. [source] Transpulmonary Stenting of Both Pulmonary Arteries with a Surgical Access through Redo SternotomyJOURNAL OF CARDIAC SURGERY, Issue 4 2009Yacine Aggoun M.D. He developed 21 months later stenosis at the origin of both pulmonary arteries. The conventional interventional catheterization approaches were not available due to femoral vein thrombosis and severe transient complete atrioventricular block due to the manipulations to catheterize the left pulmonary artery. The stenoses were treated by implant of stents using a surgical access to the proximal portion of a Contegra valved conduit (Medtronic, Inc., Minneapolis, MN, USA) by sternotomy. [source] Risk Factors for Requirement of Permanent Pacemaker Implantation After Aortic Valve ReplacementJOURNAL OF CARDIAC SURGERY, Issue 3 2006Hasan Basri Erdogan M.D. Methods: Among 465 patients operated between 1994 and 2004, 19(4.1%) patients with a mean age 49.9 ± 17.2 years required the implantation of a permanent pacemaker. Eleven of them were female (57.9%). The main indication was aortic stenosis (89.5%). Severe annular calcification was documented in 78.9% of them, and the aortic valve was bicuspid in 57.9%. Results: Risk factors for permanent pacing after aortic valve replacement (AVR) identified by univariate analysis were female sex, hypertension, preoperative ejection fraction, aortic stenosis, annular calcification, bicuspid aorta, presence of right bundle branch block (RBBB) or left bundle branch block (LBBB), prolonged aortic cross-clamp and perfusion times, and preoperative use of calcium channel blockers. Multivariate analysis showed that female sex (p = 0.01, OR; 5.21, 95% CI: 1.48-18.34), annular calcification (p < 0.001, OR; 0.05, 95% CI: 0.01-0.24), bicuspid aortic valve (p = 0.02, OR; 0.24, 95% CI: 0.07-0.84), presence of RBBB (p = 0.009, OR; 0.03, 95% CI: 0.003-0.44) or LBBB (p = 0.01, OR; 0.13, 95% CI: 0.02-0.69), hypertension (p = 0.03, OR; 0.22, 95%CI: 0.05-0.89), and total perfusion time (p = 0.002, OR; 1.05, 95% CI: 1.01-1.08) were associated risk factors. Conclusion: Irreversible atrioventricular block requiring a permanent pacemaker implantation is an uncommon complication after AVR. Risk factors are annular calcification, bicuspid aorta, female sex, presence of RBBB or LBBB, prolonged total perfusion time, and hypertension. [source] Different Forms of Ventricular Tachycardia Involving the Left Anterior Fascicle in Nonischemic Cardiomyopathy: Critical Sites of the Reentrant Circuit in Low-Voltage AreasJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2009CHRISTOPHER REITHMANN M.D. Introduction: The purpose of this study was to examine the reentrant circuit of ventricular tachycardias (VTs) involving the left anterior fascicle (LAF) in nonischemic cardiomyopathy. Methods and Results: Six patients with nonischemic cardiomyopathy presented with VTs involving the LAF. Potentials in the diastolic or presystolic phase of the VT were identified close to the LAF in 3 patients and in the mid or inferior left ventricular (LV) septum in 3 patients. Superimposed on a CARTO or NavX 3-dimensional voltage map, the diastolic and presystolic potentials were recorded within or at the border of a low-voltage zone in the LV septum in all cases. In 2 patients, both left bundle fascicles participated in the reentrant circuit including a possible interfascicular VT in one case. Ablation targeting the diastolic or presystolic potentials near the LAF or in the midinferior LV septum eliminated the VTs in all patients with the occurrence of a left posterior fascicular block and the delayed occurrence of a complete atrioventricular block in each one patient. During the follow-up of 23 ± 20 months after ablation, 4 patients were free of ventricular tachyarrhythmias. Due to detoriation of heart failure, one patient died after 12 months and one patient underwent heart transplantation after 40 months. Conclusions: Slow conduction in diseased myocardium close to the LAF or in the middle and inferior aspects of the LV septum may represent the diastolic pathway of VT involving the LAF. [source] Bepridil Reverses Atrial Electrical Remodeling and L-Type Calcium Channel Downregulation in a Canine Model of Persistent Atrial TachycardiaJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2007KUNIHIRO NISHIDA M.D. Introduction: This study tested whether bepridil, a multichannel blocker, would reverse electrical remodeling induced by persistent atrial tachycardia. Methods and Results: Fourteen dogs were subjected to rapid atrial pacing at 400 bpm for 6 weeks after atrioventricular block was created to control the ventricular rate. During the study period, seven dogs were given placebo for 6 weeks (Control group), and seven were given placebo for 3 weeks, followed by 3 weeks of bepridil (10 mg/kg/day, Bepridil group). The atrial effective refractory period (ERP) and the inducibility and duration of atrial fibrillation (AF) were determined on a weekly basis. After 6 weeks, expression of L-type calcium channel ,1C messenger ribonucleic acid (mRNA) was quantified by real-time reverse transcription-polymerase chain reaction. In the Control group, ERP was shortened and the inducibility and duration of AF increased through the 6-week period. In the Bepridil group, the same changes occurred during the first 3 weeks, but were gradually reversed with bepridil. After 6 weeks, ERP was longer, AF inducibility was lower, and AF duration was shorter in Bepridil group than in the Control group. Expression of ,1C mRNA was decreased by 64% in the Control group (P < 0.05 vs sham), but in the Bepridil group, it was not different compared with the sham dogs. As a whole group of dogs, ERP was positively correlated with ,1C mRNA expression. Conclusion: Bepridil reverses the electrophysiological consequences of atrial remodeling to some extent and L-type calcium channel downregulation in a canine model of atrial tachycardia. [source] Newly Detected Atrial Fibrillation Following Dual Chamber Pacemaker ImplantationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2006JIM W. CHEUNG M.D. Introduction: Pacemaker (PPM)-detected atrial high-rate episodes (AHREs) of even 5-minute duration may identify patients at increased risk for stroke and death. In this study, we sought to determine the incidence of newly detected atrial fibrillation (AF defined as an AHRE ,5 minutes) in patients following dual-chamber PPM implantation and to define the clinical predictors of developing AF. Methods and Results: We evaluated 262 patients (142 male; age 74 ± 12 years) without documented AF who underwent PPM implantation for sinus node dysfunction (n = 122) or atrioventricular block (n = 140). Information regarding patient demographics, cardiovascular diseases, and medication history was obtained. The cumulative percentages of ventricular pacing as well as the frequency, duration, and time to first episode of an AHRE were also determined. During follow-up of 596 ± 344 days, an AHRE ,5 minutes was detected in 77 (29%) patients. Of these, 47 (61%) patients had an AHRE ,1 hour, 22 (29%) patients had an AHRE ,1 day, and 12 (16%) patients had an AHRE ,1 week. An AHRE ,5 minutes was seen in 24% and 34% of patients at 1 year and 2 years, respectively. Among patients with sinus node dysfunction, ,50% cumulative ventricular pacing was the only significant predictor of an AHRE ,5 minutes (HR 2.2; CI 1.0,4.7; P = 0.04). Conclusions: Within 1 year of PPM implantation, AF is detected in 24% of patients without history of AF. In patients with sinus node dysfunction, ,50% cumulative right ventricular pacing is associated with a 2-fold increase in risk of developing AF. [source] Aortic Dissection and Third-Degree Atrioventricular Block in a Patient With a Hypertensive CrisisJOURNAL OF CLINICAL HYPERTENSION, Issue 1 2008Nikolaos Lionakis MD A 55-year-old man with a history of uncontrolled hypertension was admitted because of an episode of severely elevated blood pressure. An electrocardiogram revealed complete atrioventricular block while imaging showed a dissecting aneurysm of the descending thoracic and abdominal aorta, type B according to the Stanford classification. Laboratory tests revealed significant increases in serum C-reactive protein. Coronary arteriography was performed and was negative for coronary artery disease. A VDD pacemaker was placed, and a combination of 4 antihypertensive agents was used as treatment. Type B aortic dissection may present with a wide range of manifestations. The authors suggest that measurement of C-reactive protein may be used in hypertensive patients to help reflect vascular injury and its degree, progression, and prognosis. Disorders of intraventricular conductivity are rarely seen in both types of dissection of the aorta (type A, B). Atrioventricular conductivity disorders that result in complete atrioventricular block have been reported only in patients with type A dissection (before the bifurcation of the subclavian artery). In this particular case, however, the authors diagnosed an atrioventricular conductivity disorder causing atrioventricular block in a patient with type B dissection. Consequently, the authors speculate that myocardial fibrosis, as a result of long-standing hypertension, could be the main pathogenetic mechanism leading to the development of such phenomena, resulting from a potential expanding of the fibrotic process to the atrioventricular conduction system. [source] Cardiac arrest related to coronary spasm in patients with variant angina: a three-case studyJOURNAL OF INTERNAL MEDICINE, Issue 4 2002W. Seniuk We present three patients with variant angina pectoris and episodes of cardiac arrest. All of them had typical clinical symptoms, ST-segment changes in electrocardiogram, and coronary artery spasm confirmed by arteriography. They were treated with high doses of calcium antagonists and nitrates. An automatic cardioverter-defibrillator was implanted in the patient who developed ventricular fibrillation despite therapy with calcium antagonists. In another patient a DDD pacemaker was implanted because of high-degree atrioventricular block. [source] Assessment of an ECG event recorder in healthy dogs in a hospital environmentJOURNAL OF SMALL ANIMAL PRACTICE, Issue 4 2003J. M. Eastwood Ambulatory electrocardiography techniques are superior to standard electrocardiography in evaluating rhythm disturbances in dogs with episodic weakness or collapse. Disadvantages include cumbersome equipment, short recording periods and an inherent delay in trace analysis. A small programmable cardiac event recorder with combined automatic and owner-triggered recording capability was evaluated in 13 healthy dogs in a hospital environment. The unit was well tolerated and produced diagnostic recordings directly to a personal computer, with useful information about continuous heart rate. It detects premature complexes, pauses and bradycardias according to programmed detection thresholds. These events were counted frequently but trace review revealed concerns regarding specificity. Recordings were often triggered by sinus arrhythmia, sinus tachycardia and unclassifiable rate changes rather than by clinically significant arrhythmias. Correct detection of ventricular ectopic complexes, a single supraventricular premature complex, sinus arrest and second-degree atrioventricular block occurred in individual dogs. Visual review of all automatically recorded events was essential and significantly increased the time required for event recording analysis. Manual recordings might be more useful and the overall results suggest that further studies are warranted to evaluate the system in clinical cases in the home environment. [source] Cardiovascular Involvement in 8 Dogs with Blastomyces dermatitidis InfectionJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2006Chad Schmiedt Background:Blastomycosis is a common systemic fungal infection in dogs. Hypothesis:Dogs with cardiovascular involvement may have abnormalities in electrical conduction and valvular function, and may have a worse prognosis. Animals:Eight client-owned animals. Methods:Dogs with cardiovascular lesions caused by blastomycosis were identified from retrospective evaluation of medical records. Results:Five dogs had de novo infections and 3 had recurrences of previously treated infections. Harsh labored breathing, lethargy, and anorexia were the most common historic complaints. Three dogs had syncope. Physical examination and clinicopathologic data were typical of blastomycosis and included dyspnea, increased lung sounds, and lethargy. In addition, 3 dogs had heart murmurs and 1 had a third-degree atrioventricular block. Four dogs had myocarditis and 2 had pericarditis or epicarditis. Two dogs had cardiac signs attributed to extracardiac compression by fungal granulomas and clinical signs were relieved by treatment. Half of the remaining 6 dogs were euthanized; 2 of these were not treated. Of the remaining 3 dogs, 1 dog died acutely while sleeping; the second died intraoperatively during an attempt to place an epicardial pacemaker; and the third had Blastomyces -induced endocarditis and died of heart failure. Conclusions and Clinical Importance: Blastomycosis should be considered in the differential diagnosis of dogs from endemic areas with inflammatory myocarditis, heart block, heart base or intracardiac mass lesions, syncope, or endocarditis. [source] Third-Degree Atrioventricular Block in 21 Cats (1997,2004)JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2006H.B. Kellum The effect of 3rd-degree atrioventricular block on long-term outcome in cats is unknown. Clinical findings and long-term outcome of 21 cats with 3rd-degree atrioventricular block were studied retrospectively. Median age of cats studied was 14 years (range 7,19 years). Presenting signs included respiratory distress or collapse, but 6 cats had no clinical signs of disease. Eight cats had congestive heart failure (CHF) at the time that 3rd-degree atrioventricular block was detected. Heart rates ranged from 80 to 140 beats per minute (bpm; median 120 bpm) with no difference in heart rate between cats with and those without CHF. Eleven of 18 cats that had echocardiograms had structural cardiac disease, and 6 cats had cardiac changes consistent with concurrent systemic disease. No atrioventricular nodal lesions were detected by echocardiography. One cat had atrioventricular nodal lesions detected on histologic examination. Median survival of 14 cats that died or were euthanized was 386 days (range 1,2,013 days). Survival did not differ between cats with or without CHF or between cats with or without structural cardiac disease. Thirteen cats with 3rd-degree atrioventricular block survived >1 year after diagnosis, regardless of presenting signs or underlying cardiac disease. Third-degree heart block in cats is often not immediately life threatening. Survival was not affected by the presence of underlying heart disease or congestive heart failure at the time of presentation. Even cats with collapse might survive >1 year without pacemaker implantation. [source] Stepwise Transition of 2:1 Atrio-Ventricular Block to 1:1 Conduction Induced by Ventricular Premature Beats in a Patient with Atypical AVNRTPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2010ANTONIO SORGENTE M.D. A 55-year-old man with a 2-year history of recurrent paroxysmal palpitations and with an electrocardiogram documentation of atypical atrioventricular nodal re-entrant tachycardia (AVNRT) was referred to us for catheter ablation. After an initial ablation attempt, several episodes of atypical AVNRT were induced. During one of these episodes, we documented a stepwise transition of 2:1 atrioventricular block to 1:1 conduction, following two single ventricular premature beats. This phenomenon confirmed the functional nature of the AV block during AVNRT and indirectly its infra-nodal location. (PACE 2010; 33:e20,e23) [source] Initial Experience of Pacing with a Lumenless Lead System in Patients with Congenital Heart DiseasePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2009SANTABHANU CHAKRABARTI M.D. Background: Long-term pacing is frequently necessary in patients with congenital heart disease (CHD). Preservation of ventricular function and avoidance of venous occlusion is important in these patients. Site-selective pacing with a smaller diameter lead is achievable with the model 3830 lead (SelectSecure®, Medtronic Inc., Minneapolis, MN, USA), which was specifically designed to target these complications. We describe our initial experience with the Model 3830 lead in patients with CHD. Methods: Retrospective analysis of all patients undergoing site-selective implantation of a Model 3830 lead(s) from two congenital heart centers (Bristol, UK, and Dublin, Ireland) from October 2004 until February 2008. Results: We implanted 139 SelectSecure® leads (atrial n = 70; ventricular n = 69) in 90 patients (57 male) with CHD. Median age at implantation: 13.4 years (1.1,59.2 years), median weight: 43 kg. Sixty-nine patients (76%) were children (<18 years). Indications for lead implantation included atrioventricular block (n = 55), sinus node disease (n = 18), implantable cardiac defibrillator (n = 12), antitachycardia pacing (n = 4), and cardiac resynchronization (n = 1). Twenty-two patients underwent pre-existing lead extraction during the same procedure. All the attempted procedures resulted in successful pacing. One patient had a significantly raised threshold at implantation. There was no procedural mortality. There were two procedural complications. Three patients required lead repositioning for increasing thresholds early postprocedure (<6 weeks). Four leads (2.9%) had displaced on median follow-up of 21.8 months (0.5,42 months). Conclusions: The Model 3830 lead is safe and effective in patients with CHD. This is a technically challenging patient group yet procedural complication and lead displacement rates are acceptable. [source] Permanent Pacemaker Implantation Following Cardiac Surgery: Indications and Long-Term Follow-UpPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2009OFER MERIN M.D. Background: Conduction disturbances requiring permanent pacemaker implantation after heart surgery occur in about 1.5% of patients. Early pacemaker implantation may reduce morbidity and postoperative hospital stay. We reviewed our experience with patients undergoing surgery to try and identify predictors for pacemaker requirements and patients who will remain pacemaker dependent. Methods: We performed a retrospective review of 4,999 patients undergoing surgery between the years 1993 and 2005. Patient age was 64 ± 12 years, and 71% were males. Coronary bypass was performed in 4,071 (81%), aortic valve replacement in 675 (14%), and mitral valve replacement in 968 (18%) patients. Results: Seventy-two patients (1.4%) required implantation of a permanent pacemaker after surgery. Indications for pacemaker implantation included complete atrioventricular block in 59, symptomatic bradycardia/slow atrial fibrillation in nine, second-degree atrioventricular block in two, and other conduction disturbances in two patients. Predictors for pacemaker requirement by multivariate analysis were left bundle branch block and aortic valve replacement (P < 0.001). Late follow-up was available in 58 patients, at 72 ± 32 months. Thirty-seven (63%) were pacemaker dependent. Predictors for late pacemaker dependency were third-degree atrioventricular block after surgery and preoperative left bundle branch block (P < 0.001). Conclusions: Patients at high risk for pacemaker implantation after heart surgery include those with preexisting conduction disturbances, and those undergoing aortic valve replacement. Of those receiving a pacemaker, about one-third will recover at late follow-up. For patients in the high-risk group who are pacemaker dependent after surgery, we recommend implanting a permanent pacemaker at 5 days after surgery, thus enabling early mobilization and early discharge. [source] | |||||||||||||||||||||||||