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B H Rao

Publications and source records attributed to B H Rao.

25 records · Page 2Linked to original sources
PubMedDate not supplied

Radiofrequency catheter ablation of common atrial flutter--acute and follow-up results.

Atrial flutter with a structurally well-defined macro-reentrant circuit in the right atrium has recently become amenable to radiofrequency ablation with the recognition of isthmus as a narrow zone of slow conduction. This study describes 20 consecutive and symptomatic patients with atrial flutter (15 males, 5 females; mean age 38.5 +/- 10.2 years) who underwent radiofrequency ablation in our institute in the last 18 months. Fourteen patients had structurally normal hearts, while the remaining six patients had specific disorders (prior surgery for closure of atrial septal defect-2, idiopathic restrictive cardiomyopathy-1, primary sinus node dysfunction-2, tachycardiomyopathy-1). The endpoints of a complete isthmus block and conversion to sinus rhythm were achieved in 19 of the 20 patients. Total number of pulses needed to attain the endpoints was a mean of 4.2 (range 1-5), each pulse being delivered for 90 seconds. At a mean follow up of 9.4 +/- 3.2 months (range 6-12 months), recurrence of atrial flutter was seen in one patient, atrial fibrillation in two and sinus node reentrant tachycardia in one. These results are comparable to those reported in the literature. Achievement of a complete isthmus block appears to be an important endpoint in obtaining optimal results. The issues of alternative sites of ablation, long-term results and advantages of an 8 mm tip catheter need to be examined further. In conclusion, radiofrequency ablation appears to be the preferred mode of treatment for patients with atrial flutter with excellent short-term and mid-term results.

Adolescent↗
PubMedDate not supplied

Recording of double atrial potentials as a marker for isthmus block during ablation of atrial flutter.

Radiofrequency ablation is an established method for treatment of type I atrial flutter. The assessment of creation of complete bidirectional isthmus block following linear ablation of the isthmus is an integral part of ablation procedure. Conventionally, bidirectional isthmus block is tested by pacing on either side of ablation line and looking for reversal of activation sequence in the right atrium. We looked at the feasibility of recording double potentials, separated by an isoelectric interval along the ablation line as an alternative method to demonstrate bidirectional isthmus block. An attempt was made to record the double potentials following linear ablation of the cavotricuspid isthmus. Following ablation, bidirectional isthmus block was also tested by pacing from the coronary sinus os and the low-lateral right atrium. We could demonstrate double potentials in 9 of the 11 patients in whom we attempted to record them following linear ablation of flutter. The presence of bidirectional block by pacing from coronary sinus os and low lateral right atrium could be demonstrated in 10 (91%) patients. Thus, double atrial potentials, separated by an isoelectric interval can be demonstrated following ablation of atrial flutter. Double potentials, if demonstrable on coronary sinus os and low lateral right atrium pacing, could serve as an alternative marker of isthmus block.

Action Potentials↗