A survey of implanters of permanent cardiac, pacemakers during 1995 was conducted to determine pacemaker implantation rates and identify present and changing patterns in pacing practice in South Africa. The five major pacemaker manufacturers/distributors provided estimates of the numbers of implanters, implanting institutions, and pacemakers implanted in South Africa in 1995.
Background. Atrioventricular nodal re-entrant tachycardia (AVNRT) is the commonest cause of supraventricular tachycardia (SVT) and forms 35 % of our experience of SVT referred for radiofrequency (RF) ablation. We report on the results of catheter-delivered RF ablation in 93 patients (mean follow-up 20 months). There were 64 females and 29 males, mean age 46 years (range 15 - 76 years). All patients were symptomatic and in all anti-arrhythmic drug therapy had failed. Method. We used standard techniques to characterise AV nodal conduction and the variety of AVNRT. Eighty-five cases were of the common and 4 of the uncommon variety of AVNRT, 4 patients having two varieties. The site of RF application was found by combined anatomical and electro physiological mapping to locate the site of the 'slow pathway'. Success was determined by reversal of inducibility of SVT and alteration in AV nodal conduction pattern. All patients who were symptomatic after RF have undergone Holter testing.
Radiofrequency (RF) catheter ablation of an 'idiopathic' ventricular tachycardia was attempted in 18 patients. Eleven of them suffered from a ventricular outflow tract tachycardia (right ventricular outflow tract in 10 cases and left ventricular outflow tract in 1) and 7 from a fascicular left ventricular tachycardia (posterior fascicle in 6 cases and anterior fascicle in 1). The ablation was successful in all but 1 patient, who had requited a repeat procedure. All patients in whom ablation was successful remained asymptomatic without any treatment during a mean of 13.7 (SD 11.3) months of follow-up. RF catheter ablation should be considered a first-line treatment in all symptomatic patients with ventricular outflow tract tachycardia or fascicular left ventricular tachycardia.
Catheter ablation of cardiac tachyarrhythmias has been introduced to clinical cardiology on a large scale during the past decade, which has seen both an exponential increase in the number of procedures and an increasing number of indications. Results depend not only on the type of procedure but also on the operator's and the centre's experience. The estimated cumulative number of catheter ablations performed in South Africa between 1990 and 1996 is over 1 000; this does not reflect the size of the country's population, which would require about 1 000 procedures per year.