Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The principles of Fontan conversion with arrhythmia surgery are to restore the cardiac anatomy by converting the original atriopulmonary connection to a total cavopulmonary artery extracardiac connection and treat the underlying atrial arrhythmias. Successful outcomes of this procedure are dependent on a thorough understanding of several factors: the patient's fundamental diagnosis of single-ventricle anatomy, the resultant cardiac configuration from the original atriopulmonary Fontan connection, right atrial dilatation that leads to atrial flutter or fibrillation, and associated congenital cardiac anomalies. The purpose of this article is to present some of the more challenging anatomic and electrophysiologic problems we have encountered with Fontan conversion and arrhythmia surgery and the innovative solutions we have used to treat them. The cases reviewed herein include: takedown of a Bjork-Fontan modification, right ventricular hypertension and tricuspid regurgitation after atriopulmonary Fontan for pulmonary atresia and intact ventricular septum, takedown of atrioventricular valve isolation patch for right-sided maze procedure, resultant hemodynamic considerations leading to intraoperative pulmonary vein stenosis after Fontan conversion, unwanted inferior vena cava retraction during the extracardiac connection, right atrial cannulation in the presence of a right atrial clot, distended left superior vena cava causing left pulmonary vein stenosis, dropped atrial septum, and the modified right-sided maze procedure for various single-ventricle pathology. Since 1994 we have performed Fontan conversion with arrhythmia surgery on 109 patients with a 0.9% mortality rate. We attribute our program's success in no small measure to the strong collaborative efforts of the cardiothoracic surgery and cardiology teams.
 ...
PMID:Evolving anatomic and electrophysiologic considerations associated with Fontan conversion. 1743 5

The case reported herein describes the placement of a permanent transvenous pacemaker in an older dog with a previously undiagnosed persistent left cranial vena cava (PLCVC) and recent onset symptomatic third-degree atrioventricular (AV) block. On presentation the dog was found to have atrial flutter and third-degree AV block and echocardiography demonstrated evidence of chronic valvular disease and pulmonary arterial hypertension. The persistent left cranial vena cava was discovered via angiography when difficulties were encountered with pacemaker placement. Successful right ventricular pacing necessitated passage of the lead through the coronary sinus. The attendant complications in pacemaker placement in the presence of a PLCVC are well-described in man but, to the authors' knowledge, have not been described in companion animals.
 ...
PMID:Transvenous pacemaker placement in a dog with atrioventricular block and persistent left cranial vena cava. 1802 37

This chapter about antithrombotic therapy in atrial fibrillation (AF) is part of the American College of Chest Physicians Evidence-Based Guidelines Clinical Practice Guidelines (8th Edition). Grade 1 recommendations indicate that most patients would make the same choice and Grade 2 suggests that individual patient's values may lead to different choices (for a full understanding of the grading see Guyatt et al, CHEST 2008; 133[suppl]:123S-131S). Among the key recommendations in this chapter are the following (all vitamin K antagonist [VKA] recommendations have a target international normalized ratio [INR] of 2.5; range 2.0-3.0, unless otherwise noted). In patients with AF, including those with paroxysmal AF, who have had a prior ischemic stroke, transient ischemic attack (TIA), or systemic embolism, we recommend long-term anticoagulation with an oral VKA, such as warfarin, because of the high risk of future ischemic stroke faced by this set of patients (Grade 1A). In patients with AF, including those with paroxysmal AF, who have two or more of the risk factors for future ischemic stroke listed immediately below, we recommend long-term anticoagulation with an oral VKA (Grade 1A). Two or more of the following risk factors apply: age >75 years, history of hypertension, diabetes mellitus, moderately or severely impaired left ventricular systolic function and/or heart failure. In patients with AF, including those with paroxysmal AF, with only one of the risk factors listed immediately above, we recommend long-term antithrombotic therapy (Grade 1A), either as anticoagulation with an oral VKA, such as warfarin (Grade 1A), or as aspirin, at a dose of 75-325 mg/d (Grade 1B). In these patients at intermediate risk of ischemic stroke we suggest a VKA rather than aspirin (Grade 2A). In patients with AF, including those with paroxysmal AF, age < or =75 years and with none of the other risk factors listed above, we recommend long-term aspirin therapy at a dose of 75-325 mg/d (Grade 1B), because of their low risk of ischemic stroke. For patients with atrial flutter, we recommend that antithrombotic therapy decisions follow the same risk-based recommendations as for AF (Grade 1C). For patients with AF and mitral stenosis, we recommend long-term anticoagulation with an oral VKA (Grade 1B). For patients with AF and prosthetic heart valves we recommend long-term anticoagulation with an oral VKA at an intensity appropriate for the specific type of prosthesis (Grade 1B). See CHEST 2008; 133(suppl):593S-629S. For patients with AF of > or =48 h or of unknown duration for whom pharmacologic or electrical cardioversion is planned, we recommend anticoagulation with an oral VKA, such as warfarin, for 3 weeks before elective cardioversion and for at least 4 weeks after sinus rhythm has been maintained (Grade 1C). For patients with AF of > or = 48 h or of unknown duration undergoing pharmacological or electrical cardioversion, we also recommend either immediate anticoagulation with unfractionated IV heparin, or low-molecular-weight heparin (LMWH), or at least 5 days of warfarin by the time of cardioversion (achieving an INR of 2.0-3.0) as well as a screening multiplane transesophageal echocardiography (TEE). If no thrombus is seen, cardioversion is successful, and sinus rhythm is maintained, we recommend anticoagulation for at least 4 weeks. If a thrombus is seen on TEE, then cardioversion should be postponed and anticoagulation should be continued indefinitely. We recommend obtaining a repeat TEE before attempting later cardioversion (Grade 1B addressing the equivalence of TEE-guided vs non-TEE-guided cardioversion). For patients with AF of known duration <48 h, we suggest cardioversion without prolonged anticoagulation (Grade 2C). However, in patients without contraindications to anticoagulation, we suggest beginning IV heparin or LMWH at presentation (Grade 2C).
 ...
PMID:Antithrombotic therapy in atrial fibrillation: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). 1857 73

We studied the anatomic characteristics and results of surgery in 27 patients with total anomalous pulmonary venous drainage who were 15 years or older between January 1997 and July 2007. Mean age was 19.7+/-11.6 years (15-48 years). The anatomic subtypes were supracardiac (n=15), cardiac (n=7), and mixed (n=5). Fourteen patients were in NYHA class II and 13 were in NYHA class III. Eleven patients had severe and the rest had moderate pulmonary arterial hypertension; six patients had significant right ventricular dysfunction. All patients underwent complete repair. A small inter-atrial communication was left open in four patients and in two patients, a fenestrated unidirectional valved patch was used to close the atrial septal defect. There were no early or late deaths. Follow-up was 3-127 months (mean 61.2+/-36.1 months). Twenty patients were in NYHA class I and seven were in class II. Echocardiography showed normal right and left ventricular function in all patients with reduction of pulmonary arterial pressures in 26 patients. One patient underwent radiofrequency ablation for new onset atrial flutter. Surgery can be safely undertaken in a few naturally selected group of patients with total anomalous pulmonary venous drainage who survive beyond childhood.
 ...
PMID:Total anomalous pulmonary venous drainage beyond childhood. 1878 44

We describe a 42-year-old professional driver with hypertension, obesity and recurrent episodes of highly symptomatic typical atrial flutter. Despite chronic sotalol treatment, 1:1 AV conduction with RBBB-morphology was observed. After excluding of thrombus in the heart chambers, the 'urgent' and successful RF ablation was performed.
 ...
PMID:[Next cardioversion or RF ablation in professional driver with recurrent typical atrial flutter and MAS syndromes]. 1937 44

The prevalence data for atrial fibrillation (AF) are dated. The present retrospective study estimated the current and projected prevalence of AF and atrial flutter (AFL) in the United States using a large national database. Claims data drawn from July 2004 to December 2005 from the MarketScan research databases from Thomson Reuters were used to identify patients aged >or=20 years with nontransient AF and/or AFL and age- and gender-matched controls without these conditions. Of the 21,648,681 patients in the databases, 242,903 (1.12%) had nontransient AF and/or AFL (222,605 AF only, 5,376 AFL only, and 14,922 AF and AFL). Patients with AF only, AFL only, and AF and AFL had a greater (p <0.001) prevalence of co-morbidities, including hypertension (62.0%, 61.3%, and 57.0%, respectively) and coronary artery disease (43.0%, 44.7%, and 44.5%, respectively), than matched controls (45.1% hypertension and 19.4% coronary artery disease). Applying the US Census Bureau population estimates to the prevalence rates for AF and/or AFL in the databases, it was estimated that 3.03 million persons in the United States had AF only, 0.07 million had AFL only, and 0.19 million had AF and AFL in 2005. The projected prevalence for 2050 was 7.56 million for AF only, 0.15 million for AFL only, and 0.44 million for AF and AFL. In conclusion, the current prevalence of AF and AFL is high and is projected to increase considerably by 2050. The current and projected increases in the prevalence of AF are greater than predicted by a previous sentinel study and might reflect more than the aging of the population.
 ...
PMID:Increasing prevalence of atrial fibrillation and flutter in the United States. 1993 88

A 73-year-old male patient with a past history of hypertension and atrial premature contraction underwent endoscopic restoration of the left bubonocele. Sinus rhythm was confirmed by preoperative electrocardiography, but paroxysmal atrial flutter developed when abdominoscopy was started. Continuous administration of landiolol hydrochloride at a dose of 0.005 mg kg(-1) min(-1) after a loading dose of 0.04 mg kg(-1) min(-1) for 1 min resulted in control of heart rate without a decrease in blood pressure. Atrial flutter was converted to sinus rhythm 3 min after the start of administration. Landiolol hydrochloride was administered continuously until the morning of the following day and sinus rhythm was maintained postoperatively.
 ...
PMID:Conversion of atrial flutter to sinus rhythm during landiolol infusion. 2003 82

Heart hypertrophy is a common cardiac complication of sustained arterial hypertension and is accompanied by an increased incidence of supraventricular tachyarrhythmia, such as atrial fibrillation and atrial flutter. Verapamil, a phenyalkylamine, belongs to the group of calcium channel antagonists (class IV antiarrhythmic drugs) and is frequently used for the management of supraventricular tachycardia and for ventricular rate control in atrial fibrillation and atrial flutter. Verapamil heart tissue and plasma levels after intraperitoneal dosing of spontaneously hypertensive and normotensive rats were investigated. Transcript expression of various ion channels, ion transporters, calcium handling, and cytoskeletal proteins by reverse transcriptase-polymerase chain reaction (RT-PCR) were further investigated. There was no difference in plasma pharmacokinetics when hypertensive and normotensive animals were compared. Strikingly, the tissue clearance of verapamil was highly significantly impaired in heart tissue of hypertensive animals. Gene expression analysis showed the repression of many cardiac-specific genes in spontaneously hypertensive but not in normotensive rats, therefore providing evidence for different modes of action in healthy and hypertrophic hearts. Verapamil heart tissue levels differed dramatically between normotensive and hypertensive rats and resulted in repression of many cardiac ion channels, ion transporters, and calcium handling proteins. A disturbed ion homeostasis induced by critical tissue levels of verapamil is therefore proposed as a molecular rational for its pro-arrhythmogenic activity. The observed changes can be a significant determinant of spatial electrophysiological heterogeneity, thereby contributing to increased conductance disturbance as observed with some patients.
 ...
PMID:Impaired tissue clearance of verapamil in rat cardiac hypertrophy results in transcriptional repression of ion channels. 2021 36

A 48 year-old obese male with hypertension was admitted to our department because of severe right-dominant heart failure. His heart rhythm was 2:1 atrial flutter and the left ventricle was diffusely hypertrophic and hypokinetic. Primary aldosteronism was diagnosed based on severe hypokalemia (2.6 mEq/L) and a low renin-high aldosterone state with hypertension despite the use of an angiotensin-II receptor blocker, but its etiology could not be clarified with computed tomography, adrenal scintigraphy, and adrenal vein sampling. Ascites and edema rapidly worsened. Ascites aspiration was performed daily, until serum potassium was normalized by a full dose of an aldosterone receptor blocker (spironolactone 100 mg/day). A diuretic (furosemide) was then added. Rate control of atrial flutter was obtained with a beta-adrenergic blocker, and anticoagulation therapy was started. His heart failure was successfully controlled. Coronary arteries were normal on coronary arteriograms, and an endomyocardial biopsy sample obtained from the left ventricle did not show any specific pathological findings. Blood pressure was well controlled with the full dose of the aldosterone receptor blocker, but he died one year later due to intracerebral hemorrhage. As his heart failure was right dominant, we believe that its etiology may have been hyperaldosteronism-induced cardiomyopathy, and not advanced hypertensive heart disease.
 ...
PMID:Primary aldosteronism with right-dominant heart failure. 2071 49

This paper presents a summary of the evidence review group (ERG) report on the clinical effectiveness and cost-effectiveness of dronedarone for the treatment of atrial fibrillation (AF) or atrial flutter based upon a review of the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The population considered in the submission were adult clinically stable patients with a recent history of or current non-permanent AF. Comparators were the current available anti-arrhythmic drugs: class 1c agents (flecainide and propafenone), sotalol and amiodarone. Outcomes were AF recurrence, all-cause mortality, stroke, treatment discontinuations (due to any cause or due to adverse events) and serious adverse events. The main evidence came from four phase III randomised controlled trials, direct and indirect meta-analyses from a systematic review, and a synthesis of the direct and indirect evidence using a mixed-treatment comparison. Overall, the results from the different synthesis approaches showed that the odds of AF recurrence appeared statistically significantly lower with dronedarone and other anti-arrhythmic drugs than with non-active control, and that the odds of AF recurrence are statistically significantly higher for dronedarone than for amiodarone. However, the results for outcomes of all-cause mortality, stroke and treatment discontinuations and serious adverse events were all uncertain. A discrete event simulation model was used to evaluate dronedarone versus antiarrhythmic drugs and standard therapy alone. The incremental cost-effectiveness ratio of dronedarone was relatively robust and less than 20,000 pounds per quality-adjusted life-year. Exploratory work undertaken by the ERG identified that the main drivers of cost-effectiveness were the benefits assigned to dronedarone for all-cause mortality and stroke. Dronedarone is not cost-effective relative to its comparators when the only effect of treatment is a reduction in AF recurrences. In conclusion, uncertainties remain in the clinical effectiveness and cost-effectiveness of dronedarone. In particular, the clinical evidence for the major drivers of cost-effectiveness (all-cause mortality and stroke), and consequently the additional benefits attributed in the economic model to dronedarone compared to other anti-arrhythmic drugs are highly uncertain. The final guidance, issued by NICE on 25 August 2010, states that: Dronedarone is recommended as an option for the treatment of non-permanent atrial fibrillation only in people: whose atrial fibrillation is not controlled by first-line therapy (usually including beta-blockers), that is, as a second-line treatment option, and who have at least one of the following cardiovascular risk factors: - hypertension requiring drugs of at least two different classes, diabetes mellitus, previous transient ischaemic attack, stroke or systemic embolism, left atrial diameter of 50 mm or greater, left ventricular ejection fraction less than 40% (noting that the summary of product characteristics [SPC] does not recommend dronedarone for people with left ventricular ejection fraction less than 35% because of limited experience of using it in this group) or age 70 years or older, and who do not have unstable New York Heart Association (NYHA) class III or IV heart failure. Furthermore, 'People who do not meet the criteria above who are currently receiving dronedarone should have the option to continue treatment until they and their clinicians consider it appropriate to stop'.
 ...
PMID:Dronedarone for the treatment of atrial fibrillation and atrial flutter. 2104 92


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>