The Lambeth Conventions are guidelines intended to be of practical value in the investigation of arrhythmias induced by ischaemia, infarction, and reperfusion. They cover the design and execution of experiments and the definition, classification, quantification, and analysis of arrhythmias. Investigators are encouraged to adopt the conventions in the hope that this will improve uniformity and interlaboratory comparisons.

The serum concentration of C-reactive protein was prospectively assessed in 37 patients with various degrees of heart failure. The serum concentration of Creactive protein was higher than normal in 26 (70%/0) patients. The concentration was directly related to the severity of heart failure and the stage of decompensation. Hepatic cell damage is the most likely stimulus to cytokine production and hence release of C-reactive protein in heart failure. Heart failure is an additional cause of raised serum concentration of C-reactive protein but the pathological importance of this feature is not yet known.

SUMMARY The diagnostic and therapeutic potential of intravenous adenosine was studied in 64 patients during 92 episodes of regular sustained tachycardia. In 40 patients who had narrow complex tachycardias (QRS <0-12 s) adenosine (2-5-25 mg) restored sinus rhythm in 25 with junctional tachycardias (46 of 48 episodes) and produced atrioventricular block to reveal atrial or sinus tachycardia in 15. In 24 patients with broad complex tachycardias (QRS > 0 12 s) adenosine terminated the tachycardias in six patients and revealed atrial or sinus arrhythmias in four. The tachycardias persisted in 14 patients despite doses up to 20 mg, but adenosine allowed the diagnosis of ventricular tachycardia with retrograde atrial activation in two patients by producing transient ventriculoatrial dissociation. Diagnosis based on adenosine induced atrioventricular nodal block was correct in all patients with narrow complex tachycardias and in 92% of those with broad complex tachycardias, compared with correct electrocardiographic diagnoses in 90% and 75% respectively. Adenosine gave diagnostic information additional to the electrocardiogram in 25%. The response to adenosine in broad complex tachycardias identified those of supraventricular origin with 90% sensitivity, 93% specificity, and 92% predictive accuracy. Adenosine restored sinus rhythm in all patients with junctional reentrant tachycardias, but in 10 (35%) the arrhythmias recurred within two minutes. Symptomatic side effects (dyspnoea, chest pain, flushing, headache) were reported by 40 (63%) patients and, although transient, were severe in 23 (36%). There were ventricular pauses ofover 2 s in 16% of patients, the longest pause being 6*1 s.Adenosine is ofvalue in the diagnosis and treatment of narrow and broad complex tachycardias, but its use is limited by symptomatic side effects, a tenfold range in minimal effective dosage, occasional action at sites other than the atrioventricular node, and early recurrence of arrhythmia.Adenosine is a naturally occurring, rapidly metabolised compound that produces transient atrioventricular nodal block in humans when injected intravenously.' It can terminate reentrant supraventricular tachycardias that involve the atrioventricular node,' while in tachycardias of atrial origin it may be of diagnostic value, because adenosine induced atrioventricular block slows the ventricular rate and reveals the unaffected atrial arrhythmia.2 Such diagnostic and therapeutic effects of adenosine should be of most value in broad complex Requests for reprints to Dr A C Rankin,

No abstract

No abstract