PubMed Health⌕ Search

Biomedical subjects

G C Kaye

Publications and source records attributed to G C Kaye.

At least 19 recordsLinked to original sources

Giant right coronary artery aneurysm presenting as a mediastinal mass.

Coronary artery aneurysms are commonly of atherosclerotic origin and are frequently asymptomatic. However, they may have varied presentations including angina, myocardial infarction, and sudden death. A case of a giant right coronary artery aneurysm presenting with acute myocardial infarction is presented, where the aneurysm appeared to be a mediastinal mass on transthoracic and transoesophageal echocardiography. Although computed tomography and magnetic resonance imaging of the heart suggested the correct diagnosis, definitive proof came from coronary angiography. Coronary artery aneurysms should be considered in the differential diagnosis of mediastinal masses.

Aged↗

Successful use of oral linezolid as a single active agent in endocarditis unresponsive to conventional antibiotic therapy.

Treatment of resistant gram-positive endocarditis is difficult. We report a case of resistant Staphylococcus epidermidis endocarditis that failed to respond to conventional antibiotic therapy but was treated successfully with an oral regimen of a new antibiotic, linezolid as a single active agent. This case report demonstrates the use of linezolid as an effective alternative to conventional antibiotics in such cases.

Acetamides↗

An unusual case of infective endocarditis.

A rare case of Corynebacterium striatum endocarditis on a bioprosthetic aortic valve replacement, treated medically, is reported. The presentation was subacute, and initially endocarditis screening was negative. Because of the failure of symptoms to settle further screening was performed which confirmed the organism in several sets of blood cultures. This emphasises the importance of persistent screening for endocarditis if the history raises any suspicion of this potentially serious infection, especially in the presence of prosthetic valves.

Aortic Valve↗

Clinical use of intracardiac impedance: current applications and future perspectives.

For over 40 years the measurement of intracardiac impedance has been proposed as a method of assessing the contractile state of the heart muscle. This technique requires the positioning of one or more intracavitary electrodes and the generation of an electric field from an alternating current source. Variations in the calculated impedance signal reflect changes in the ventricular blood pool volume adjacent to the electrodes. Intracardiac impedance measurement has been successfully developed as a research tool to assess myocardial contractility, and from this, clinical uses have evolved. Commercial rate responsive pacing systems use intracardiac impedance to assess the inotropic state of the heart. Further development of this technology might allow hemodynamic discrimination of cardiac arrhythmias.

Animals↗

Hyperkalemia diagnosed by implantable cardioverter defibrillator T wave sensing.

A patient with congestive heart failure and an ICD had undergone atrioventricular nodal ablation and optimization of heart failure medical therapy. Intracardiac T wave sensing by the ICD drew attention to the new development of asymptomatic hyperkalemia. Surface ECG features of hyperkalemia were not readily identified due to pacemaker dependence.

Defibrillators, Implantable↗

Systematic review of the management of atrial fibrillation in patients with heart failure.

AIMS: To systematically review the management of atrial fibrillation (AF) in patients with heart failure. METHODS: Studies investigating the management of AF in patients with heart failure published between 1967 to 1998 were identified using MEDLINE, the Cochrane register and Embase databases. Reference lists from relevant papers and reviews were hand searched for further papers. RESULTS: Eight studies pertaining to acute and twenty-four pertaining to chronic AF were identified. For patients with acute AF ventricular rate control, anticoagulation and treatment of heart failure should be pursued simultaneously before cardioversion is attempted. Digoxin is relatively ineffective at controlling ventricular response and for cardioversion. Intravenous diltiazem is rapidly effective in controlling ventricular rate and limited evidence suggests it is safe. Amiodarone controls ventricular rate rapidly and increases the rate of cardioversion. There are insufficient data to conclude that immediate anti-coagulation, trans-oesophageal echocardiography to exclude atrial thrombi followed by immediate cardioversion is an appropriate strategy. Patients with chronic AF should be anti-coagulated unless contra-indications exist. It is not clear whether the preferred strategy should be cardioversion and maintenance of sinus rhythm with amiodarone or ventricular rate control of AF combined with anticoagulation to improve outcome including symptoms, morbidity and survival. Electrical cardioversion has a high initial success rate but there is also a high risk of early relapse. Amiodarone currently appears the most effective and safest therapy for maintaining sinus rhythm post-cardioversion. Digoxin is fairly ineffective at controlling ventricular rate during exercise. Addition of a beta-blocker reduces ventricular rate and improves symptoms. Whether digoxin is required in addition to beta-blockade for the control of AF in this setting is currently under investigation. If pharmacological therapy is ineffective or not tolerated then atrio-ventricular node ablation and permanent pacemaker implantation should be considered. CONCLUSION: There is a paucity of controlled clinical trial data for the management of AF among patients with heart failure. The interaction between AF and heart failure means that neither can be treated optimally without treating both. Presently treatment should be on a case by case basis.

Acute Disease↗

The measurement of impedance to assess myocardial contractility and rhythm stability.

By introducing an alternating current through the ventricular cavity via a multipolar catheter the potential difference measured between adjacent electrodes can be used to assess ventricular volume. This is possible by the measurement of intracardiac impedance. The data obtained can be used to construct pressure-volume loops allowing the continuous real-time assessment of myocardial contractility. Clinical applications of this research tool are now becoming apparent. Further derivations of impedance measurement have been incorporated into commercially available permanent pacing systems, allowing effective heart rate modulation.

Electric Impedance↗